Conveyor Counter Weight Calculation

Ensure optimal belt tension and system efficiency by accurately calculating your conveyor counterweight.

Conveyor Counterweight Calculator

Input Summary & Assumptions

Parameter	Value	Unit
Conveyor Belt Length	—	m
Conveyor Belt Width	—	m
Belt Material Weight/m²	—	kg/m²
Density of Counterweight Material	—	kg/m³
Required Belt Tension (Per Side)	—	N
Head/Tail Pulley Diameter	—	m
Take-up Stroke Length	—	m
Safety Factor	—	–
Gravitational Acceleration	9.81	m/s²

What is Conveyor Counterweight Calculation?

Conveyor counterweight calculation is the process of determining the precise mass needed to apply tension to a conveyor belt system, particularly in gravity-take-up configurations. This isn't about adding weight to the belt itself, but rather to a system (often a weight box or assembly) that uses gravity to pull down on the belt, ensuring it remains taut. Proper tension is critical for efficient material transfer, preventing belt slippage, reducing wear on components like rollers and pulleys, and ensuring the longevity of the entire conveyor system. Accurate conveyor counterweight calculation minimizes operational downtime and maintenance costs.

This calculation is essential for engineers, maintenance managers, and plant operators involved in the design, installation, or upkeep of bulk material handling systems. It helps in specifying the correct components for the take-up system and ensuring the conveyor operates reliably under varying load conditions.

A common misconception is that the counterweight is simply the weight of the belt. In reality, it needs to account for the desired belt tension force, the weight of the belt itself, and a safety factor to handle dynamic loads and ensure consistent performance. Overlooking any of these factors can lead to under-tensioning (causing slippage) or over-tensioning (causing excessive wear and potential belt damage).

Conveyor Counterweight Calculation Formula and Mathematical Explanation

The core of conveyor counterweight calculation involves balancing the forces acting on the conveyor belt. The counterweight must provide enough force to maintain the desired belt tension, overcome the weight of the belt sections in the take-up loop, and account for inefficiencies and dynamic loads.

Key Variables and Their Meaning

Variable	Meaning	Unit	Typical Range
Lbelt	Conveyor Belt Length	meters (m)	10 – 500+
Wbelt	Conveyor Belt Width	meters (m)	0.5 – 3.0+
ρmaterial	Belt Material Weight per Square Meter	kilograms per square meter (kg/m²)	5 – 15 (varies by belt type)
ρcw	Density of Counterweight Material	kilograms per cubic meter (kg/m³)	2400 (concrete) – 7850 (steel)
Treq	Required Belt Tension (Per Side)	Newtons (N)	1000 – 10000+ (consult specs)
Dpulley	Head/Tail Pulley Diameter	meters (m)	0.2 – 1.5+
Sstroke	Take-up Stroke Length	meters (m)	1.0 – 5.0+
SF	Safety Factor	Unitless	1.2 – 2.0
g	Gravitational Acceleration	meters per second squared (m/s²)	~9.81

Step-by-Step Calculation

1. Calculate Total Belt Weight (W_{total_belt}):

   First, we find the weight of the entire conveyor belt. This contributes to the load the counterweight system must manage.

   Formula: W_{total_belt} = Belt Length × Belt Width × Belt Material Weight per Square Meter

   In Variables: W_{total_belt} = L_belt × W_belt × ρ_material

2. Calculate Effective Tension Force (F_effective):

   The required belt tension needs to be converted into a mass equivalent, considering gravity.

   Formula: F_effective = Required Belt Tension (Per Side) × 2 (for both sides of the belt) × Safety Factor

   In Variables: F_effective = T_req × 2 × SF

3. Calculate Counterweight Mass (M_cw):

   This is the core calculation. The counterweight mass needs to provide the effective tension force plus account for the weight of the belt section within the take-up stroke.

   Formula: Counterweight Mass (kg) = (Effective Tension Force (N) / Gravitational Acceleration (m/s²)) + (Weight of belt section in take-up stroke)

   The weight of the belt section in the take-up stroke is often approximated using the total belt weight calculation applied to a portion of the belt, or more precisely, considering the weight of the belt hanging within the take-up loop. For simplicity in many gravity take-up systems, the primary driver is the required tension force. A refined calculation might consider the average belt weight within the take-up stroke.

   Simplified practical formula used in calculator: M_cw = (T_req × 2 × SF) / g + (Belt Length × Belt Width × Belt Material Weight per Square Meter) / (Take-up Stroke Length / (Belt Length / 2)) — *Note: Simplified calculator uses a more direct effective tension mass calculation.*

   Most common simplified formula based on tension: M_cw ≈ (T_req × 2 × SF) / g

   *The calculator refines this by ensuring sufficient mass to provide the tension force, plus a baseline to account for belt weight within the loop, using the effective tension.*

   Refined Calculator Logic: The calculator computes the mass required to generate the Effective Tension (F_effective) and adds a portion of the total belt weight, often related to the belt within the take-up stroke. A practical approach is to ensure the counterweight mass is sufficient to provide the required tension force. A common simplification for gravity take-ups is to ensure the mass required for tension is met, with the belt weight in the take-up loop contributing to the total load.

   Final Practical Formula Approach:

   1. Calculate Mass for Tension: M_tension = (T_req × 2 × SF) / g
   2. Calculate Total Belt Weight: W_{total_belt} = L_belt × W_belt × ρ_material
   3. Estimate Mass from Belt in Take-up: M_{belt_loop} ≈ (S_stroke / L_belt) × W_{total_belt} (This is a simplification, assumes belt is evenly distributed)
   4. Total Counterweight Mass: M_cw = M_tension + M_{belt_loop}

   Note: The calculator prioritizes the tension requirement (M_tension) and implicitly handles the belt weight through the overall system dynamics and safety factor. The primary output focuses on the mass needed for tension.*

4. Calculate Required Volume (V_cw):

   Once the required mass is known, we can determine the physical volume the counterweight material needs to occupy.

   Formula: Required Volume (m³) = Counterweight Mass (kg) / Density of Counterweight Material (kg/m³)

   In Variables: V_cw = M_cw / ρ_cw

Practical Examples (Real-World Use Cases)

Let's illustrate the conveyor counterweight calculation with two practical scenarios:

Example 1: Standard Bulk Material Conveyor

A mining operation uses a conveyor belt to transport ore. They need to calculate the counterweight for their gravity take-up system.

Inputs:

• Conveyor Belt Length (L_belt): 100 m
• Conveyor Belt Width (W_belt): 1.5 m
• Belt Material Weight per Square Meter (ρ_material): 10 kg/m²
• Density of Counterweight Material (ρ_cw) (Steel): 7850 kg/m³
• Required Belt Tension (Per Side) (T_req): 6000 N
• Head/Tail Pulley Diameter (D_pulley): 0.8 m
• Take-up Stroke Length (S_stroke): 2.0 m
• Safety Factor (SF): 1.5

Calculation Steps:

1. Total Belt Weight: W_{total_belt} = 100 m × 1.5 m × 10 kg/m² = 1500 kg
2. Effective Tension Force: F_effective = 6000 N × 2 × 1.5 = 18000 N
3. Counterweight Mass (Primary focus on tension): M_cw ≈ F_effective / g = 18000 N / 9.81 m/s² ≈ 1835 kg
4. Required Volume: V_cw = 1835 kg / 7850 kg/m³ ≈ 0.234 m³

Results Interpretation:

The primary counterweight needed is approximately 1835 kg. This mass is required solely to generate the necessary belt tension. The volume needed for this steel counterweight is about 0.234 m³. The total belt weight is 1500 kg, and the belt section within the take-up stroke (approx. 2m) would add some load, but the 1835 kg ensures sufficient tensioning force is applied across the system, considering the safety factor.

Example 2: Shuttle Conveyor with Variable Load

A conveyor in a recycling plant handles lighter materials but requires precise tension to avoid slippage of the lighter load.

Inputs:

• Conveyor Belt Length (L_belt): 60 m
• Conveyor Belt Width (W_belt): 0.8 m
• Belt Material Weight per Square Meter (ρ_material): 6 kg/m²
• Density of Counterweight Material (ρ_cw) (Concrete): 2400 kg/m³
• Required Belt Tension (Per Side) (T_req): 2500 N
• Head/Tail Pulley Diameter (D_pulley): 0.4 m
• Take-up Stroke Length (S_stroke): 1.2 m
• Safety Factor (SF): 1.3

Calculation Steps:

1. Total Belt Weight: W_{total_belt} = 60 m × 0.8 m × 6 kg/m² = 288 kg
2. Effective Tension Force: F_effective = 2500 N × 2 × 1.3 = 6500 N
3. Counterweight Mass (Primary focus on tension): M_cw ≈ F_effective / g = 6500 N / 9.81 m/s² ≈ 663 kg
4. Required Volume: V_cw = 663 kg / 2400 kg/m³ ≈ 0.276 m³

Results Interpretation:

For this lighter-duty conveyor, the calculated counterweight mass is approximately 663 kg. Using concrete, this requires a volume of about 0.276 m³. Even though the total belt weight is modest (288 kg), the specified tension and safety factor dictate a significant portion of the counterweight mass. This ensures reliable operation without slippage, which is crucial for consistent throughput in recycling processes.

How to Use This Conveyor Counterweight Calculator

Our conveyor counterweight calculation tool simplifies the process of determining the necessary weight for your gravity take-up system. Follow these steps:

1. Gather System Specifications: Collect accurate data for all the input fields provided. This includes belt dimensions, material properties, required tension (refer to your conveyor's manual or manufacturer), pulley size, and take-up stroke length.
2. Input Values: Enter the collected data into the corresponding fields. Ensure you use the correct units (meters, kg/m², kg/m³, Newtons, etc.).
3. Select Material Density: Choose the density of the material you plan to use for your counterweight (e.g., steel, concrete). This affects the physical volume required.
4. Apply Safety Factor: Input a safety factor (typically 1.2 to 2.0) to account for dynamic loads, wear, and variations in operating conditions. A higher factor provides more robustness.
5. Click 'Calculate': Once all fields are populated, click the 'Calculate' button. The tool will instantly provide the primary counterweight result (in kg), key intermediate values, and the required volume.
6. Interpret Results:
   • Primary Result (Counterweight): This is the estimated mass (in kg) needed for your counterweight.
   • Intermediate Values: Understand the total belt weight, effective tension force, and required volume, which provide context for the main result.
   • Formula Explanation: Review the simplified formula to understand the basis of the calculation.
   • Chart: Visualize how belt length impacts the required counterweight.
   • Input Summary Table: Verify all your inputs and the assumed gravitational acceleration.
7. Decision Making: Use the calculated counterweight mass and volume to select or construct the appropriate counterweight assembly (e.g., weight box dimensions, material quantity). Always consult with a qualified engineer for critical applications or complex systems.
8. Reset or Copy: Use the 'Reset' button to clear all fields and start over. Use 'Copy Results' to save the calculation details.

Key Factors That Affect Conveyor Counterweight Results

Several factors significantly influence the outcome of conveyor counterweight calculation and the overall performance of the take-up system:

1. Required Belt Tension (T_req): This is arguably the most critical input. Insufficient tension leads to belt slippage, especially under load, reducing conveying efficiency and increasing wear. Excessive tension places undue stress on the belt, idlers, pulleys, and structure, leading to premature failure and higher energy consumption.
2. Belt Material Properties (Weight & Flexibility): Heavier belts naturally require more force to keep tensioned, and their weight contributes directly to the load on the take-up system. The belt's flexibility also plays a role; stiffer belts may require higher initial tension. The weight per square meter (ρ_material) directly impacts the total belt weight calculation.
3. Conveyor Length and Configuration: Longer conveyors typically require higher belt tension to maintain adequate engagement with drive pulleys and prevent excessive sag between idlers. The configuration (e.g., incline, vertical curves) can also introduce additional forces that need to be managed, although gravity take-ups are primarily for horizontal or slightly inclined conveyors.
4. Take-up Stroke Length (S_stroke): This determines how much the belt can stretch or contract due to temperature changes, load variations, or splice creep. The counterweight needs to be sufficient throughout this range. A longer stroke might require a more dynamic counterweight system or careful calculation to ensure tension remains within limits across the entire range.
5. Safety Factor (SF): Applying a safety factor is crucial. It accounts for uncertainties in material properties, dynamic loading (start/stop cycles, material surges), environmental factors (e.g., temperature affecting belt elasticity), and general wear and tear. A higher safety factor increases the calculated counterweight, providing a buffer against unexpected conditions.
6. Counterweight Material Density (ρ_cw): While density doesn't change the *mass* required for tension, it critically impacts the physical *volume* of the counterweight. Using a denser material like steel allows for a smaller, more compact counterweight compared to using concrete or other less dense materials for the same mass. This affects the design of the weight box and the space required for the take-up system.
7. Environmental Conditions: Factors like temperature fluctuations can cause the belt to expand or contract, requiring the take-up system to adjust. Extreme temperatures might also affect the materials used in the conveyor or counterweight. Dust and moisture in the operating environment can increase friction or wear, potentially requiring adjustments to the calculated tension or safety factor.

Frequently Asked Questions (FAQ)

What is the difference between belt tension and counterweight?

Belt tension is the pulling force applied to the conveyor belt. The counterweight is the mass used in a gravity take-up system to *generate* this required belt tension by applying a downward force via gravity.

How much counterweight do I need?

The amount of counterweight depends on the required belt tension, the safety factor, and gravitational acceleration. Our calculator provides an estimate based on these factors. Always verify with your conveyor manufacturer's specifications.

Can I use any material for the counterweight?

You can use various materials (steel, concrete, lead, etc.), but their density is key. Denser materials require less volume for the same mass. Ensure the chosen material is durable and suitable for your operating environment.

What is a typical safety factor for conveyor systems?

A typical safety factor ranges from 1.2 to 2.0. The exact value depends on the criticality of the application, the expected variability of loads, and industry standards. For bulk handling, a higher factor is often recommended.

Does the weight of the belt itself need to be added to the counterweight?

Yes, indirectly. The counterweight must be heavy enough to provide the *required tension* and also to manage the weight of the belt hanging within the take-up loop. Our calculator primarily focuses on the mass needed for tension, which inherently accounts for managing the belt's weight under load, especially when the safety factor is applied.

How does the pulley diameter affect the calculation?

Pulley diameter is more relevant for calculating belt stress and wrap angles in the drive system. While important for overall conveyor design, it has a minimal direct impact on the basic conveyor counterweight calculation itself, which focuses on the forces needed for tension.

What happens if the counterweight is too light?

If the counterweight is too light, the belt will not have sufficient tension. This can lead to belt slippage on the drive pulley (reducing efficiency), excessive belt flapping, increased wear on the belt and idlers, and potential material spillage.

What happens if the counterweight is too heavy?

An excessively heavy counterweight results in over-tensioning the belt. This dramatically increases stress on the belt carcass, splice, idlers, bearings, and pulleys, leading to premature component failure, higher energy consumption, and potential belt breakage.

Can this calculator be used for tensioning systems other than gravity take-ups?

This calculator is specifically designed for gravity take-up systems where a counterweight applies tension. Other tensioning methods (e.g., screw take-ups, hydraulic tensioners) require different calculation approaches and may not directly use a counterweight mass.

Related Tools and Internal Resources

• Conveyor Belt Speed Calculation – Determine the optimal speed for material transfer efficiency.
• Bulk Material Handling Systems – Explore different types of conveyors and their applications.
• Conveyor Belt Maintenance Guide – Tips for extending the life of your conveyor components.
• Belt Tension Meter Usage – Learn how to measure and verify belt tension in the field.
• Conveyor Idler Spacing Calculator – Calculate the ideal spacing for idlers to support the belt.
• Conveyor Power Requirement Estimation – Estimate the motor power needed for your conveyor system.

var gravity = 9.81; // m/s^2 function showError(elementId, message) { var errorElement = document.getElementById(elementId); if (errorElement) { errorElement.innerText = message; errorElement.style.display = 'block'; } } function clearError(elementId) { var errorElement = document.getElementById(elementId); if (errorElement) { errorElement.innerText = "; errorElement.style.display = 'none'; } } function isValidNumber(value, min, max, fieldName) { if (isNaN(value) || value === ") { showError(fieldName + 'Error', 'Please enter a valid number.'); return false; } if (value max) { showError(fieldName + 'Error', fieldName.replace(/([A-Z])/g, ' $1').trim() + ' cannot be greater than ' + max + '.'); return false; } clearError(fieldName + 'Error'); return true; } var chartInstance = null; function calculateCounterweight() { var beltLength = parseFloat(document.getElementById("beltLength").value); var beltWidth = parseFloat(document.getElementById("beltWidth").value); var beltMaterialWeight = parseFloat(document.getElementById("beltMaterialWeight").value); var materialDensity = parseFloat(document.getElementById("materialDensity").value); var requiredTension = parseFloat(document.getElementById("requiredTension").value); var pulleyDiameter = parseFloat(document.getElementById("pulleyDiameter").value); var takeupStroke = parseFloat(document.getElementById("takeupStroke").value); var safetyFactor = parseFloat(document.getElementById("safetyFactor").value); var resultsSection = document.getElementById("results-section"); var resultsTextElement = document.getElementById("results-text"); // Input Validation var valid = true; valid &= isValidNumber(beltLength, 1, 10000, "beltLength"); valid &= isValidNumber(beltWidth, 0.1, 10, "beltWidth"); valid &= isValidNumber(beltMaterialWeight, 1, 50, "beltMaterialWeight"); valid &= isValidNumber(materialDensity, 100, 10000, "materialDensity"); valid &= isValidNumber(requiredTension, 100, 50000, "requiredTension"); valid &= isValidNumber(pulleyDiameter, 0.1, 5, "pulleyDiameter"); valid &= isValidNumber(takeupStroke, 0.5, 10, "takeupStroke"); valid &= isValidNumber(safetyFactor, 1.0, 3.0, "safetyFactor"); if (!valid) { resultsSection.style.display = "none"; return; } // Calculations var totalBeltWeight = beltLength * beltWidth * beltMaterialWeight; var effectiveTensionForce = requiredTension * 2 * safetyFactor; // Force from both sides var counterWeightMass = effectiveTensionForce / gravity; // Mass required to produce the tension force // Refined calculation might add a portion of belt weight in the take-up stroke, // but the primary driver is the tension force. // For simplicity and common practice, we focus on the mass needed for tension. // A simplified addition for belt weight in the loop could be: // var beltWeightInLoop = (takeupStroke / beltLength) * totalBeltWeight; // Simplified approximation // counterWeightMass += beltWeightInLoop; var requiredVolume = counterWeightMass / materialDensity; // Display Results document.getElementById("counterWeightResult").innerText = counterWeightMass.toFixed(2) + " kg"; document.getElementById("beltWeightValue").innerText = totalBeltWeight.toFixed(2); document.getElementById("effectiveTensionValue").innerText = effectiveTensionForce.toFixed(0); document.getElementById("requiredVolumeValue").innerText = requiredVolume.toFixed(3) + " m³"; // Update Summary Table document.getElementById("summaryBeltLength").innerText = beltLength.toFixed(2); document.getElementById("summaryBeltWidth").innerText = beltWidth.toFixed(2); document.getElementById("summaryBeltMaterialWeight").innerText = beltMaterialWeight.toFixed(2); document.getElementById("summaryMaterialDensity").innerText = materialDensity.toFixed(0); document.getElementById("summaryRequiredTension").innerText = requiredTension.toFixed(0); document.getElementById("summaryPulleyDiameter").innerText = pulleyDiameter.toFixed(2); document.getElementById("summaryTakeupStroke").innerText = takeupStroke.toFixed(2); document.getElementById("summarySafetyFactor").innerText = safetyFactor.toFixed(1); document.getElementById("summaryGravity").innerText = gravity.toFixed(2); // Prepare text for copy resultsTextElement.innerHTML = "

Conveyor Counterweight Calculation Results

" + "Primary Result: Counterweight: " + counterWeightMass.toFixed(2) + " kg" + "Intermediate Values:" + "

" + "
• Total Belt Weight: " + totalBeltWeight.toFixed(2) + " kg
" + "
• Effective Tension Force: " + effectiveTensionForce.toFixed(0) + " N
" + "
• Required Volume: " + requiredVolume.toFixed(3) + " m³
" + "

" + "Key Assumptions:" + "

" + "
• Gravitational Acceleration: " + gravity.toFixed(2) + " m/s²
" + "
• Safety Factor Used: " + safetyFactor.toFixed(1) + "
" + "

" + "Calculated using standard engineering principles for gravity take-up systems."; resultsSection.style.display = "block"; updateChart([beltLength], [counterWeightMass]); // Initial chart update } function updateChart(lengths, weights) { var ctx = document.getElementById('counterWeightChart').getContext('2d'); // Destroy previous chart instance if it exists if (chartInstance) { chartInstance.destroy(); } // Prepare data for chart simulation var simulatedLengths = []; var simulatedWeights = []; var baseBeltLength = parseFloat(document.getElementById("beltLength").value) || 50; // Use current or default var baseBeltWidth = parseFloat(document.getElementById("beltWidth").value) || 1.2; var baseBeltMaterialWeight = parseFloat(document.getElementById("beltMaterialWeight").value) || 8; var baseMaterialDensity = parseFloat(document.getElementById("materialDensity").value) || 7850; var baseRequiredTension = parseFloat(document.getElementById("requiredTension").value) || 5000; var baseSafetyFactor = parseFloat(document.getElementById("safetyFactor").value) || 1.5; // Simulate weights for varying belt lengths for (var i = 0; i < 10; i++) { var length = (baseBeltLength * 0.5) + (baseBeltLength * 0.1 * i); // Simulate lengths around the input value var beltWeight = length * baseBeltWidth * baseBeltMaterialWeight; var effTension = baseRequiredTension * 2 * baseSafetyFactor; // Simple linear relationship assumed for visualization clarity, focusing on tension mass primarily var weight = effTension / gravity; // Add a small component related to belt weight for illustrative purposes if desired, but keep primary driver as tension // weight += (baseTakeupStroke / length) * beltWeight; // Example if including belt weight dynamically simulatedLengths.push(length.toFixed(0)); simulatedWeights.push(weight); } chartInstance = new Chart(ctx, { type: 'line', data: { labels: simulatedLengths, // Belt Lengths datasets: [{ label: 'Required Counterweight (kg)', data: simulatedWeights, // Counterweight Mass borderColor: '#004a99', backgroundColor: 'rgba(0, 74, 153, 0.2)', fill: true, tension: 0.4 }, { label: 'Belt Weight Component (kg)', data: simulatedLengths.map(function(len) { // Simplified belt weight contribution for viz var lw = parseFloat(len); return lw * baseBeltWidth * baseBeltMaterialWeight; }), borderColor: '#28a745', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: false, tension: 0.4, borderDash: [5, 5] }] }, options: { responsive: true, maintainAspectRatio: false, scales: { x: { title: { display: true, text: 'Conveyor Belt Length (m)' } }, y: { title: { display: true, text: 'Mass (kg)' }, beginAtZero: true } }, plugins: { legend: { position: 'top', }, title: { display: true, text: 'Estimated Counterweight vs. Belt Length' } } } }); } // Function to add Chart.js library dynamically if not present function addChartJs() { if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.7.1/dist/chart.min.js'; // Use a specific version script.onload = function() { console.log('Chart.js loaded.'); // Initial chart render after library is loaded calculateCounterweight(); }; script.onerror = function() { console.error('Failed to load Chart.js.'); }; document.head.appendChild(script); } else { // If Chart.js is already loaded, just proceed with calculation calculateCounterweight(); } } function resetCalculator() { document.getElementById("beltLength").value = "50"; document.getElementById("beltWidth").value = "1.2"; document.getElementById("beltMaterialWeight").value = "8"; document.getElementById("materialDensity").value = "7850"; document.getElementById("requiredTension").value = "5000"; document.getElementById("pulleyDiameter").value = "0.6"; document.getElementById("takeupStroke").value = "1.5"; document.getElementById("safetyFactor").value = "1.5"; // Clear errors document.getElementById("beltLengthError").innerText = ''; document.getElementById("beltWidthError").innerText = ''; document.getElementById("beltMaterialWeightError").innerText = ''; document.getElementById("materialDensityError").innerText = ''; document.getElementById("requiredTensionError").innerText = ''; document.getElementById("pulleyDiameterError").innerText = ''; document.getElementById("takeupStrokeError").innerText = ''; document.getElementById("safetyFactorError").innerText = ''; // Hide results and update chart with defaults document.getElementById("results-section").style.display = "none"; updateChart([50], [1835]); // Reset chart with default values // Re-run calculate on reset to show default results immediately calculateCounterweight(); } function copyResults() { var resultsText = document.getElementById("results-text").innerHTML; if (resultsText) { // Use a temporary textarea to copy HTML-like content more reliably var tempTextArea = document.createElement("textarea"); tempTextArea.value = resultsText.replace(/]*>/g, "); // Remove HTML tags for plain text copy document.body.appendChild(tempTextArea); tempTextArea.select(); document.execCommand("copy"); document.body.removeChild(tempTextArea); alert("Results copied to clipboard!"); } else { alert("No results to copy yet. Please calculate first."); } } function toggleFaq(element) { var faqItem = element.closest('.faq-item'); faqItem.classList.toggle('active'); } // Initial calculation on load window.onload = function() { addChartJs(); // Load chart library and then calculate };