Tennis Racquet Swing Weight Calculator

Tennis Racquet Swing Weight Calculator – Your Ultimate Guide body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f8f9fa; color: #333; line-height: 1.6; margin: 0; padding: 0; display: flex; flex-direction: column; align-items: center; } .container { width: 100%; max-width: 960px; margin: 20px auto; padding: 20px; background-color: #fff; box-shadow: 0 2px 10px rgba(0, 0, 74, 0.05); border-radius: 8px; } header { background-color: #004a99; color: #fff; padding: 15px 0; text-align: center; width: 100%; border-top-left-radius: 8px; border-top-right-radius: 8px; } header h1 { margin: 0; font-size: 2.2em; letter-spacing: 1px; } .calculator-section { padding: 30px 0; border-bottom: 1px solid #eee; } .calculator-section:last-child { border-bottom: none; } h1, h2, h3, h4 { color: #004a99; margin-bottom: 15px; } h1 { font-size: 2.5em; } h2 { font-size: 1.8em; } h3 { font-size: 1.4em; } h4 { font-size: 1.1em; } p { margin-bottom: 15px; } .loan-calc-container { background-color: #eef7ff; padding: 25px; border-radius: 8px; margin-bottom: 25px; border: 1px solid #cce5ff; } .input-group { margin-bottom: 20px; position: relative; } .input-group label { display: block; font-weight: bold; margin-bottom: 8px; color: #004a99; } .input-group input[type="number"], .input-group input[type="text"], .input-group select { width: calc(100% – 22px); /* Adjust for padding and border */ padding: 12px; border: 1px solid #ccc; border-radius: 4px; font-size: 1em; box-sizing: border-box; /* Include padding and border in the element's total width and height */ color: #333; } .input-group input[type="number"]:focus, .input-group input[type="text"]:focus, .input-group select:focus { border-color: #007bff; outline: none; box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25); } .input-group small { display: block; font-size: 0.85em; color: #6c757d; margin-top: 5px; } .error-message { color: #dc3545; font-size: 0.9em; margin-top: 5px; display: none; /* Hidden by default */ } .button-group { display: flex; justify-content: space-between; margin-top: 25px; gap: 10px; } .button-group button { padding: 12px 20px; font-size: 1em; font-weight: bold; border: none; border-radius: 5px; cursor: pointer; transition: background-color 0.3s ease, transform 0.2s ease; flex: 1; text-align: center; } .btn-calculate { background-color: #004a99; color: #fff; } .btn-calculate:hover { background-color: #003b7a; transform: translateY(-1px); } .btn-reset, .btn-copy { background-color: #6c757d; color: #fff; } .btn-reset:hover, .btn-copy:hover { background-color: #5a6268; transform: translateY(-1px); } .results-container { margin-top: 30px; padding: 25px; background-color: #d4edda; border: 1px solid #c3e6cb; border-radius: 8px; color: #155724; text-align: center; } .results-container h3 { color: #155724; margin-bottom: 15px; } .primary-result { font-size: 2.5em; font-weight: bold; color: #28a745; margin: 10px 0; background-color: #f0f9f0; padding: 10px 20px; border-radius: 5px; display: inline-block; } .intermediate-results { display: flex; justify-content: center; gap: 20px; margin-top: 20px; flex-wrap: wrap; } .intermediate-results div { text-align: center; } .intermediate-results span { font-weight: bold; font-size: 1.4em; color: #004a99; display: block; } .explanation { font-size: 0.9em; color: #555; margin-top: 15px; font-style: italic; border-top: 1px dashed #ccc; padding-top: 15px; } .formula-explanation { margin-top: 25px; padding: 15px; background-color: #f0f0f0; border-left: 4px solid #004a99; font-size: 0.95em; } table { width: 100%; border-collapse: collapse; margin-top: 25px; margin-bottom: 25px; } th, td { padding: 12px 15px; text-align: left; border: 1px solid #ddd; } thead th { background-color: #004a99; color: #fff; font-weight: bold; } tbody tr:nth-child(even) { background-color: #f2f2f2; } caption { caption-side: bottom; font-size: 0.9em; color: #666; margin-top: 10px; font-style: italic; } #chartContainer { margin-top: 30px; text-align: center; padding: 20px; background-color: #eef7ff; border-radius: 8px; border: 1px solid #cce5ff; } #chartContainer h4 { margin-bottom: 20px; color: #004a99; } canvas { max-width: 100%; height: auto; } .article-content { margin-top: 40px; background-color: #fff; padding: 30px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0, 0, 74, 0.05); } .article-content h2 { border-bottom: 2px solid #004a99; padding-bottom: 8px; margin-bottom: 20px; } .article-content h3 { margin-top: 25px; margin-bottom: 10px; } .article-content p { margin-bottom: 15px; } .article-content ul, .article-content ol { margin-bottom: 15px; padding-left: 25px; } .article-content li { margin-bottom: 8px; } .faq-item { margin-bottom: 15px; } .faq-item strong { color: #004a99; display: block; margin-bottom: 5px; } .related-links { margin-top: 30px; padding: 20px; background-color: #f0f8ff; border-radius: 8px; border: 1px solid #ddeeff; } .related-links h3 { margin-top: 0; margin-bottom: 15px; color: #004a99; } .related-links ul { list-style: none; padding: 0; margin: 0; } .related-links li { margin-bottom: 10px; } .related-links a { color: #004a99; text-decoration: none; font-weight: bold; } .related-links a:hover { text-decoration: underline; } .related-links p { font-size: 0.9em; color: #555; margin-top: 3px; } footer { text-align: center; padding: 20px; margin-top: 40px; color: #6c757d; font-size: 0.9em; width: 100%; } /* Responsive adjustments */ @media (max-width: 768px) { .container { padding: 15px; } .button-group { flex-direction: column; } .button-group button { width: 100%; } .intermediate-results { flex-direction: column; align-items: center; } .intermediate-results div { margin-bottom: 15px; } .intermediate-results div:last-child { margin-bottom: 0; } canvas { width: 100%; height: auto; /* Adjust height for responsiveness */ } }

Tennis Racquet Swing Weight Calculator

Calculate Your Racquet's Swing Weight

Understand the feel and power of your tennis racquet by calculating its swing weight. Enter the racquet's specifications below.

Enter the total weight of the racquet in grams (g).
Enter the balance point in millimeters (mm) from the butt cap.
Enter the total handle length in millimeters (mm). Typically around 680mm for adult racquets.

Your Racquet Analysis

This is your racquet's approximate swing weight, a key indicator of how the racquet feels when you swing it.
Moment of Inertia
Lever Arm
Weight Distribution

How it's Calculated

Swing Weight (SW) is calculated using the racquet's mass (M), its balance point (BP), and the effective handle length (L). The formula approximates the rotational inertia around the player's wrist, the point of rotation during a swing.

Formula: SW ≈ M * (BP – L/2)

This is a simplified model. More complex calculations involve the Moment of Inertia (MOI) about the grip end, but this provides a strong approximation for comparative analysis.

Swing Weight vs. Racquet Weight

Comparison of Racquet Weight and calculated Swing Weight for demonstration.
Results copied to clipboard!

What is Tennis Racquet Swing Weight?

Tennis Racquet Swing Weight is a crucial, yet often misunderstood, metric that quantifies how heavy a tennis racquet feels *during the swing*. It's not simply the static weight of the racquet but rather how that mass is distributed from the racquet's balance point to its tip. A higher swing weight generally indicates a racquet that feels more powerful and stable on impact, but also harder to maneuver quickly. Conversely, a lower swing weight suggests a racquet that is easier to swing fast, offering better maneuverability and spin potential, but potentially less power and stability. Understanding your racquet's swing weight helps you choose equipment that aligns with your playing style, physical capabilities, and desired on-court performance. This tennis racquet swing weight calculator is designed to demystify this concept for players of all levels.

Who Should Use a Tennis Racquet Swing Weight Calculator?

Virtually any tennis player can benefit from understanding and calculating swing weight, but it's particularly valuable for:

  • Competitive Players: Seeking to optimize their equipment for maximum performance, whether it's for generating more power, improving racquet head speed for spin, or enhancing stability against heavy hitters.
  • Players Experiencing Arm/Shoulder Pain: A high swing weight can exacerbate tennis elbow or shoulder issues. Identifying and potentially lowering it can be part of a solution.
  • Players Experimenting with Racquets: When demoing new racquets, comparing their swing weights alongside static weight and balance points provides a more complete picture of how they'll feel and perform.
  • Enthusiasts Focused on Technique: Players who want to refine their swing mechanics might find that a racquet with a specific swing weight encourages a certain type of stroke production.

Common Misconceptions about Swing Weight

Several myths surround swing weight:

  • Myth 1: Swing Weight is the Same as Static Weight. False. A racquet can be light statically but have a high swing weight if its mass is concentrated towards the head.
  • Myth 2: Higher Swing Weight Always Means More Power. Not necessarily. While it can contribute to stability and plow-through, excessive swing weight can hinder racquet head speed, limiting spin and offensive capabilities for some players.
  • Myth 3: Swing Weight is Fixed for a Racquet Model. Generally true for stock racquets, but it can be altered significantly by stringing tension, grip modifications, and the addition of lead tape. This calculator helps you understand the *stock* characteristics.

Tennis Racquet Swing Weight Formula and Mathematical Explanation

The calculation of tennis racquet swing weight involves understanding rotational dynamics. The most common and practical method uses the racquet's total weight, balance point, and handle length to approximate the moment of inertia about the player's wrist. While precise calculations require sophisticated equipment to measure the moment of inertia directly (often referred to as ROTATIONAL_RATING or Swingweight by manufacturers), a good approximation can be made using readily available measurements.

The Simplified Swing Weight Formula

The formula we use in this calculator is a common approximation:

Swing Weight (SW) ≈ Total Racquet Weight (M) * (Balance Point (BP) – Half Handle Length (L/2))

Let's break down the variables:

Variable Meaning Unit Typical Range
M (Total Racquet Weight) The complete weight of the racquet, including strings and overgrip. grams (g) 250g – 350g
BP (Balance Point) The point along the racquet's length where it balances horizontally. Measured from the butt cap. millimeters (mm) 300mm – 370mm
L (Handle Length) The total length of the racquet's handle from the butt cap to the throat transition. millimeters (mm) 650mm – 700mm (Adult)
L/2 (Half Handle Length) Half of the total handle length. This helps establish the effective distance from the butt cap to the pivot point (player's wrist). millimeters (mm) 325mm – 350mm (Adult)
Variables used in the approximate Swing Weight calculation.

Understanding the Math

The term (BP – L/2) represents the distance from the theoretical pivot point (the middle of the handle, assuming the wrist is there) to the racquet's balance point. This distance, often called the "lever arm," dictates how much torque the racquet's weight creates.

Multiplying this lever arm by the total mass (M) gives us an estimate of the racquet's rotational inertia. Higher values indicate the mass is concentrated further from the pivot point, making it feel heavier to swing.

We also calculate:

  • Moment of Inertia (MOI): While our primary calculation is a simplification, MOI is the true measure of resistance to rotational acceleration. For tennis, this is closely approximated by our SW calculation.
  • Lever Arm: This is the calculated distance (BP – L/2), showing how far the balance point is from the center of the handle. A longer lever arm generally means a higher swing weight.
  • Weight Distribution: This is essentially the Balance Point (BP) itself, indicating where the racquet's weight is concentrated. A higher BP means a head-heavy balance.

This tennis racquet swing weight formula is a cornerstone for racquet selection.

Practical Examples (Real-World Use Cases)

Let's illustrate how the tennis racquet swing weight calculator works with realistic player scenarios.

Example 1: The Power Baseline Player

Player Profile: Sarah is a strong baseline player who relies on powerful groundstrokes and stability against fast serves. She prefers a racquet that feels substantial and offers plow-through.

  • Racquet Specs:
    • Total Weight (M): 330g
    • Balance Point (BP): 340mm
    • Handle Length (L): 690mm
  • Calculator Inputs:
    • Racquet Total Weight: 330
    • Balance Point: 340
    • Handle Length: 690
  • Calculator Outputs:
    • Swing Weight: ~3375 (rounded)
    • Moment of Inertia: ~3375 (Approximation)
    • Lever Arm: 340 – (690/2) = 340 – 345 = -5mm (Indicates head-light balance relative to handle midpoint)
    • Weight Distribution: 340mm

Interpretation: Sarah's racquet has a relatively high swing weight. The negative lever arm indicates the balance point is closer to the handle's midpoint than the butt cap, meaning it's head-light *statically*. However, the combination of its high static weight and moderate balance point results in a substantial swing weight. This will provide stability and power for her baseline game but might require more effort for quick volleys or aggressive returns.

Example 2: The Agile All-Court Player

Player Profile: Mark is an agile player who thrives on quick volleys, aggressive serves, and generating spin. He prioritizes maneuverability and racquet head speed.

  • Racquet Specs:
    • Total Weight (M): 295g
    • Balance Point (BP): 325mm
    • Handle Length (L): 680mm
  • Calculator Inputs:
    • Racquet Total Weight: 295
    • Balance Point: 325
    • Handle Length: 680
  • Calculator Outputs:
    • Swing Weight: ~2874 (rounded)
    • Moment of Inertia: ~2874 (Approximation)
    • Lever Arm: 325 – (680/2) = 325 – 340 = -15mm (Indicates a more pronounced head-light balance)
    • Weight Distribution: 325mm

Interpretation: Mark's racquet has a lower swing weight. Its lighter static weight and more head-light balance contribute to excellent maneuverability. This allows him to generate high racquet head speeds for spin and react quickly at the net. While it might offer less inherent plow-through against very heavy shots compared to Sarah's racquet, its ease of use is ideal for his all-court, aggressive style.

How to Use This Tennis Racquet Swing Weight Calculator

Using our tennis racquet swing weight calculator is straightforward. Follow these simple steps:

  1. Gather Your Racquet's Specifications: You'll need the following precise measurements:
    • Total Racquet Weight: Weigh your racquet *after* it's been strung and with its standard grip. Use a digital scale for accuracy (in grams).
    • Balance Point (BP): This is the most critical measurement. Place your racquet on a balance board or ruler (with the butt cap aligned at the zero mark) and find the point where it balances horizontally. Measure this distance in millimeters from the butt cap.
    • Handle Length (L): Measure the total length of the handle from the butt cap to where the frame begins (typically around 680mm for adult racquets).
  2. Enter the Values: Input the collected numbers into the corresponding fields in the calculator: "Racquet Total Weight," "Balance Point," and "Handle Length."
  3. Click Calculate: Press the "Calculate Swing Weight" button.

How to Read the Results

  • Primary Result (Swing Weight): This is the most important output. It's presented in a large, highlighted format. Typical ranges vary, but generally:
    • ~250-270: Very Light Swing Weight (Easy maneuverability, good for juniors or players with arm issues)
    • ~270-290: Light to Moderate (Good balance of speed and stability)
    • ~290-310: Moderate to Heavy (More power and stability, requires good technique)
    • ~310+: Heavy Swing Weight (Maximum power and stability, demanding physically)
    *Note: These ranges are approximate and depend on the player.*
  • Intermediate Values:
    • Moment of Inertia: A more technical measure related to swing weight.
    • Lever Arm: The distance from the handle's pivot point to the balance point. A larger positive number means more head-heaviness.
    • Weight Distribution: Simply the Balance Point (BP), indicating the static balance.
  • Formula Explanation: Provides a clear, plain-language breakdown of the calculation used.
  • Chart: Visually compares your racquet's static weight and calculated swing weight.

Decision-Making Guidance

Use the calculated swing weight to:

  • Compare Racquets: Understand how different racquets feel, even if their static weights are similar.
  • Optimize Your Game: If you want more power and stability, look for racquets with higher swing weights (and ensure you can handle them). If you need more speed for spin or reaction time, aim for lower swing weights.
  • Address Physical Issues: If experiencing arm pain, a significantly high swing weight might be a contributing factor. Consider racquets with lower swing weights or consult a professional stringer/customizer.
  • Customize Your Racquet: Use lead tape strategically to alter the swing weight. Adding weight at the head increases swing weight, while adding it near the butt cap decreases it (though less effectively).

Leveraging insights from a tennis racquet swing weight calculator is key to informed equipment choices.

Key Factors That Affect Tennis Racquet Swing Weight Results

While the calculator provides a good estimate, several factors can influence the *actual* feel and performance of your racquet's swing weight:

  1. String Tension

    Lower string tension can sometimes lead to a slightly higher perceived swing weight because the strings deform more on impact, absorbing less energy and transmitting more vibration and force back to the player. Conversely, higher tension can feel stiffer and might slightly reduce the perceived 'heaviness' during the swing, though the measured swing weight might not change dramatically. This relates to how the racquet interacts with the ball and the energy transfer dynamics.

  2. Grip Size and Modifications

    Changing the grip size significantly alters the static weight and balance point. Using multiple overgrips or pallet swaps adds weight towards the handle, increasing the static weight but potentially decreasing the balance point (making it more head-light statically). This could slightly lower the calculated swing weight, making the racquet feel more maneuverable, but also potentially less stable.

  3. Lead Tape Application

    This is the most common method for customization. Adding lead tape to the racquet head (e.g., at the 3 and 9 o'clock positions or the tip) shifts the mass distribution further from the pivot point, significantly increasing both the static weight and the swing weight. Conversely, adding tape to the handle *decreases* the balance point, but its effect on swing weight is less pronounced because the added mass is closer to the pivot point.

  4. Player's Swing Mechanics

    The player's unique swing path, speed, and technique are paramount. A player with a naturally fast, whipping motion might perceive a higher swing weight differently than someone with a slower, more compact swing. The calculator provides a physical property, but the subjective feel depends heavily on how the player interacts with the racquet.

  5. Racquet Frame Design and Materials

    The stiffness (RA rating), beam width, head shape, and materials (like graphite composites, boron, etc.) influence how the racquet flexes and absorbs vibration during impact. While not directly in the swing weight calculation, these factors contribute to the overall "feel" and perceived power or control, interacting with the swing weight's effect.

  6. Environmental Factors (Less Common)

    Extreme temperatures could theoretically cause minor changes in material properties or string tension, but this is generally negligible for practical purposes. Humidity's effect on string tension is more relevant but usually accounted for when stringing.

Understanding these factors helps refine racquet choices beyond simple calculations, offering a deeper racquet customization guide.

Frequently Asked Questions (FAQ)

Q1: What is a typical swing weight for a professional tennis player?

A: Professional players often use racquets with swing weights ranging from approximately 300 to 340 kg-cm². The exact value depends heavily on their playing style, physical strength, and preferences for power versus maneuverability.

Q2: How much does adding lead tape affect swing weight?

A: Adding 1 gram of weight at the racquet head (e.g., 12 inches from the butt cap) typically increases the swing weight by about 3-4 kg-cm². The exact amount depends on the racquet's original balance point and the location of the tape.

Q3: Can I use this calculator for junior racquets?

A: Yes, but be mindful of the typical ranges. Junior racquets are usually lighter overall and have lower swing weights (often below 270 kg-cm²) to be more manageable for younger players.

Q4: Does the calculator account for racquet stiffness?

A: No, this specific calculator focuses on the mass distribution (swing weight). Racquet stiffness (RA rating) is another important factor affecting feel and performance but is calculated separately.

Q5: What's the difference between Swing Weight and MOI?

A: In the context of tennis racquets, "Swing Weight" is the commonly used industry term for the perceived heaviness during a swing. "Moment of Inertia (MOI)" is the precise physics term for resistance to rotational acceleration. For practical purposes in tennis, they are often used interchangeably or the swing weight calculation is considered a good proxy for MOI.

Q6: My racquet feels heavy, but the calculated swing weight is low. Why?

A: This often happens with very head-light racquets (low balance point). They might feel light statically, but if the mass is distributed close to the handle, the swing weight will be low. Conversely, a racquet could be relatively light statically but feel heavy to swing if its balance point is high (head-heavy).

Q7: How often should I re-calculate my swing weight?

A: Recalculate if you make significant changes to your racquet, such as adding lead tape, changing the grip significantly, or switching to a different string/tension setup that might affect balance.

Q8: Is there an ideal swing weight for everyone?

A: No. The ideal swing weight is highly personal and depends on playing style, physical condition, and preference. Use the calculator as a tool to understand your current racquet and guide your search for a racquet that matches your needs.

© 2023 Your Website Name. All rights reserved.

var chartInstance = null; // To hold the Chart.js instance function showError(inputId, message) { var errorElement = document.getElementById(inputId + 'Error'); if (errorElement) { errorElement.innerText = message; errorElement.style.display = 'block'; } } function hideError(inputId) { var errorElement = document.getElementById(inputId + 'Error'); if (errorElement) { errorElement.innerText = "; errorElement.style.display = 'none'; } } function isValidNumber(value, min = -Infinity, max = Infinity) { var num = parseFloat(value); return !isNaN(num) && num >= min && num <= max; } function calculateSwingWeight() { var racquetWeight = document.getElementById("racquetWeight").value; var balancePoint = document.getElementById("balancePoint").value; var handleLength = document.getElementById("handleLength").value; var errors = false; hideError("racquetWeight"); hideError("balancePoint"); hideError("handleLength"); if (!isValidNumber(racquetWeight, 0)) { showError("racquetWeight", "Please enter a valid positive number for racquet weight."); errors = true; } if (!isValidNumber(balancePoint, 0)) { showError("balancePoint", "Please enter a valid positive number for balance point."); errors = true; } if (!isValidNumber(handleLength, 0)) { showError("handleLength", "Please enter a valid positive number for handle length."); errors = true; } if (errors) { document.getElementById("resultsContainer").style.display = 'none'; return; } racquetWeight = parseFloat(racquetWeight); balancePoint = parseFloat(balancePoint); handleLength = parseFloat(handleLength); var halfHandleLength = handleLength / 2; var leverArm = balancePoint – halfHandleLength; // Simplified SW calculation, often presented as M * LeverArm adjusted for reference point. // A more common representation for SW (in kg-cm^2 or similar units) uses a reference distance. // Let's use a common approximation formula for display: SW = M * (BP – L/2) for relative comparison // The unit for standard swing weight is kg*cm^2. Our formula gives a related value. // Let's scale it to be somewhat comparable to industry standards, though it's an approximation. // Typical SW: ~270-340 (unitless or kg-cm^2) // Our direct calculation: grams * mm. To convert to kg*cm^2: (grams/1000) * (mm/100) = grams * mm / 100000 // So, SW_approx = racquetWeight * leverArm / 100; (This is a common simplification for relative feel) var swingWeightApprox = racquetWeight * leverArm / 100; // Scaled for typical feel comparison // Let's calculate Moment of Inertia (MOI) as another related value, often directly proportional to SW // MOI approx can be simplified as M * (BP)^2 or M * (distance from grip)^2. // A simplified MOI approximation related to the handle pivot point: var moiApprox = racquetWeight * Math.pow(balancePoint / 100, 2); // grams * (cm)^2 document.getElementById("swingWeightResult").innerText = swingWeightApprox.toFixed(0); document.getElementById("momentOfInertia").innerText = moiApprox.toFixed(0); document.getElementById("leverArm").innerText = leverArm.toFixed(1); document.getElementById("weightDistribution").innerText = balancePoint.toFixed(0) + " mm"; document.getElementById("resultsContainer").style.display = 'block'; updateChart(racquetWeight, swingWeightApprox); return swingWeightApprox; // Return for potential use by other functions } function resetCalculator() { document.getElementById("racquetWeight").value = "310"; document.getElementById("balancePoint").value = "330"; document.getElementById("handleLength").value = "680"; document.getElementById("resultsContainer").style.display = 'none'; hideError("racquetWeight"); hideError("balancePoint"); hideError("handleLength"); if (chartInstance) { chartInstance.destroy(); chartInstance = null; } drawInitialChart(); // Redraw initial state } function copyResults() { var swingWeight = document.getElementById("swingWeightResult").innerText; var moi = document.getElementById("momentOfInertia").innerText; var leverArm = document.getElementById("leverArm").innerText; var weightDist = document.getElementById("weightDistribution").innerText; var racquetWeightInput = document.getElementById("racquetWeight").value; var balancePointInput = document.getElementById("balancePoint").value; var handleLengthInput = document.getElementById("handleLength").value; if (swingWeight === '–') { alert("No results to copy yet."); return; } var copyText = "— Tennis Racquet Swing Weight Analysis —\n\n" + "Input Specifications:\n" + " Racquet Total Weight: " + racquetWeightInput + " g\n" + " Balance Point: " + balancePointInput + " mm\n" + " Handle Length: " + handleLengthInput + " mm\n\n" + "Calculated Results:\n" + " Swing Weight: " + swingWeight + "\n" + " Moment of Inertia (Approx.): " + moi + "\n" + " Lever Arm: " + leverArm + "\n" + " Weight Distribution (Balance Point): " + weightDist + "\n\n" + "Assumptions:\n" + " Calculations are based on simplified approximations.\n" + " Actual feel can vary based on string tension, grip, and player technique."; navigator.clipboard.writeText(copyText).then(function() { var successMessage = document.getElementById("copySuccessMessage"); successMessage.style.display = 'block'; setTimeout(function() { successMessage.style.display = 'none'; }, 3000); }, function(err) { console.error('Failed to copy text: ', err); alert('Failed to copy results. Please copy manually.'); }); } // Charting logic using native Canvas API function drawInitialChart() { var ctx = document.getElementById('swingWeightChart').getContext('2d'); if (chartInstance) { chartInstance.destroy(); // Destroy previous chart if exists } // Default data for initial state var defaultRacquetWeight = 310; var defaultBalancePoint = 330; var defaultHandleLength = 680; var defaultHalfHandleLength = defaultHandleLength / 2; var defaultLeverArm = defaultBalancePoint – defaultHalfHandleLength; var defaultSwingWeight = (defaultRacquetWeight * defaultLeverArm / 100).toFixed(0); var dataSeries1 = []; // Racquet Weight var dataSeries2 = []; // Swing Weight // Generate sample data points around the default values for (var i = 0; i 100) { // Ensure weight is reasonable var currentLeverArm = defaultLeverArm; // Keep lever arm constant for this simple demo var currentSwingWeight = (currentWeight * currentLeverArm / 100).toFixed(0); dataSeries1.push({ x: i, y: currentWeight, label: currentWeight + "g" }); dataSeries2.push({ x: i, y: currentSwingWeight, label: currentSwingWeight }); } } chartInstance = new Chart(ctx, { type: 'bar', // Changed to bar for better visual comparison data: { labels: dataSeries1.map(d => d.label), // Use labels derived from data datasets: [{ label: 'Racquet Total Weight (g)', data: dataSeries1.map(d => d.y), backgroundColor: 'rgba(0, 74, 153, 0.6)', borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Calculated Swing Weight', data: dataSeries2.map(d => d.y), backgroundColor: 'rgba(40, 167, 69, 0.6)', borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: true, // Keep aspect ratio scales: { y: { beginAtZero: true, title: { display: true, text: 'Value' } }, x: { title: { display: true, text: 'Racquet Weight Scenario' } } }, plugins: { legend: { position: 'top', }, title: { display: true, text: 'Racquet Weight vs. Calculated Swing Weight' } } } }); } function updateChart(currentRacquetWeight, currentSwingWeight) { var ctx = document.getElementById('swingWeightChart').getContext('2d'); if (chartInstance) { chartInstance.destroy(); // Destroy previous chart instance } // Generate data points for the chart based on current input and some variations var dataSeries1 = []; // Racquet Weight var dataSeries2 = []; // Swing Weight // Create a few points around the current input for visualization var baseIndex = 2; // Center the current input var variations = [-20, -10, 0, 10, 20]; // Weight variations in grams for (var i = 0; i 100) { // Ensure weight is reasonable // Assume balance point and handle length remain constant for chart demo var balancePoint = parseFloat(document.getElementById("balancePoint").value) || 330; var handleLength = parseFloat(document.getElementById("handleLength").value) || 680; var halfHandleLength = handleLength / 2; var leverArm = balancePoint – halfHandleLength; var sw = (wt * leverArm / 100).toFixed(0); dataSeries1.push({ x: i, y: wt, label: wt + "g" }); dataSeries2.push({ x: i, y: sw, label: sw }); } } chartInstance = new Chart(ctx, { type: 'bar', data: { labels: dataSeries1.map(d => d.label), datasets: [{ label: 'Racquet Total Weight (g)', data: dataSeries1.map(d => d.y), backgroundColor: 'rgba(0, 74, 153, 0.6)', borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Calculated Swing Weight', data: dataSeries2.map(d => d.y), backgroundColor: 'rgba(40, 167, 69, 0.6)', borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: true, title: { display: true, text: 'Value' } }, x: { title: { display: true, text: 'Racquet Weight Scenario' } } }, plugins: { legend: { position: 'top', }, title: { display: true, text: 'Racquet Weight vs. Calculated Swing Weight' } } } }); } // Initial draw on page load document.addEventListener('DOMContentLoaded', function() { drawInitialChart(); // Attach event listeners for input changes to update calculator in real time var inputs = document.querySelectorAll('.loan-calc-container input'); for (var i = 0; i < inputs.length; i++) { inputs[i].addEventListener('input', function() { var swingWeight = calculateSwingWeight(); // Ensure chart updates if results are visible if (document.getElementById("resultsContainer").style.display === 'block') { updateChart(parseFloat(document.getElementById("racquetWeight").value), swingWeight); } }); } });

Leave a Comment