Price per Weight Calculator App

Price Per Weight Calculator App – Find the Best Value :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #dee2e6; –card-bg: #ffffff; –shadow: 0 2px 10px rgba(0, 0, 0, 0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); line-height: 1.6; margin: 0; padding: 20px; display: flex; flex-direction: column; align-items: center; } .container { width: 100%; max-width: 960px; background-color: var(–card-bg); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-bottom: 30px; } h1, h2, h3 { color: var(–primary-color); text-align: center; margin-bottom: 20px; } h1 { font-size: 2.5em; } h2 { font-size: 2em; border-bottom: 2px solid var(–primary-color); padding-bottom: 10px; margin-top: 40px; } h3 { font-size: 1.5em; margin-top: 30px; } .calculator-section { background-color: var(–card-bg); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-bottom: 30px; } .calculator-section h2 { text-align: left; margin-bottom: 25px; } .loan-calc-container { display: flex; flex-direction: column; gap: 20px; } .input-group { display: flex; flex-direction: column; gap: 8px; } .input-group label { font-weight: bold; color: var(–primary-color); } .input-group input[type="number"], .input-group input[type="text"], .input-group select { padding: 12px; border: 1px solid var(–border-color); border-radius: 4px; font-size: 1em; width: 100%; box-sizing: border-box; } .input-group input[type="number"]:focus, .input-group input[type="text"]:focus, .input-group select:focus { outline: none; border-color: var(–primary-color); box-shadow: 0 0 0 2px rgba(0, 74, 153, 0.2); } .input-group .helper-text { font-size: 0.85em; color: #6c757d; } .error-message { color: #dc3545; font-size: 0.85em; margin-top: 5px; display: none; /* Hidden by default */ } .button-group { display: flex; gap: 10px; margin-top: 20px; flex-wrap: wrap; /* Allow buttons to wrap on smaller screens */ } .button-group button { padding: 12px 20px; border: none; border-radius: 4px; cursor: pointer; font-size: 1em; font-weight: bold; transition: background-color 0.3s ease; flex-grow: 1; /* Allow buttons to grow and fill space */ } .btn-calculate { background-color: var(–primary-color); color: white; } .btn-calculate:hover { background-color: #003366; } .btn-reset { background-color: #6c757d; color: white; } .btn-reset:hover { background-color: #5a6268; } .btn-copy { background-color: #ffc107; color: #212529; } .btn-copy:hover { background-color: #e0a800; } #results { margin-top: 30px; padding: 25px; background-color: #e7f1ff; border: 1px solid #b3d7ff; border-radius: 8px; text-align: center; } #results h3 { margin-top: 0; color: var(–primary-color); font-size: 1.8em; } .main-result { font-size: 2.5em; font-weight: bold; color: var(–success-color); margin: 15px 0; padding: 15px; background-color: white; border-radius: 6px; display: inline-block; } .intermediate-results { display: flex; flex-wrap: wrap; justify-content: center; gap: 20px; margin-top: 20px; } .intermediate-results div { background-color: white; padding: 15px 20px; border-radius: 6px; border: 1px solid var(–border-color); text-align: center; min-width: 150px; } .intermediate-results div span { display: block; font-size: 1.8em; font-weight: bold; color: var(–primary-color); } .formula-explanation { margin-top: 20px; font-style: italic; color: #6c757d; } table { width: 100%; border-collapse: collapse; margin-top: 25px; box-shadow: var(–shadow); } th, td { padding: 12px; text-align: left; border: 1px solid var(–border-color); } thead { background-color: var(–primary-color); color: white; } tbody tr:nth-child(even) { background-color: #eef3f7; } caption { font-size: 1.1em; font-weight: bold; color: var(–primary-color); margin-bottom: 15px; text-align: left; } #chartContainer { width: 100%; margin-top: 25px; background-color: var(–card-bg); padding: 20px; border-radius: 8px; box-shadow: var(–shadow); } #chartContainer canvas { width: 100% !important; /* Ensure canvas takes full width */ height: auto !important; } .chart-caption { font-size: 1.1em; font-weight: bold; color: var(–primary-color); margin-bottom: 15px; text-align: left; } .article-content { width: 100%; max-width: 960px; background-color: var(–card-bg); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 30px; text-align: left; } .article-content p { margin-bottom: 15px; } .article-content a { color: var(–primary-color); text-decoration: none; font-weight: bold; } .article-content a:hover { text-decoration: underline; } .faq-section h3 { text-align: left; } .faq-section p { font-weight: bold; margin-top: 15px; margin-bottom: 5px; } .faq-section span { font-weight: normal; } .related-links ul { list-style: none; padding: 0; } .related-links li { margin-bottom: 10px; } .main-result-unit { font-size: 1.2em; font-weight: normal; color: var(–text-color); } .intermediate-results div span .unit { font-size: 0.7em; font-weight: normal; color: var(–text-color); display: block; } @media (min-width: 768px) { .container { padding: 40px; } .calculator-section { padding: 40px; } .article-content, .container { padding: 50px; } } .copy-message { display: none; color: var(–success-color); font-weight: bold; margin-top: 10px; text-align: center; }

Price Per Weight Calculator App

Easily compare products and find the best value for your money by calculating the price per unit of weight.

Price Per Weight Calculator

Enter the total price of the first product.
Enter the total weight of the first product.
grams (g) kilograms (kg) ounces (oz) pounds (lb) milliliters (ml) – for liquids liters (l) – for liquids fluid ounces (fl oz) – for liquids gallons (gal) – for liquids Select the unit of weight for the first product.
Enter the total price of the second product.
Enter the total weight of the second product.
grams (g) kilograms (kg) ounces (oz) pounds (lb) milliliters (ml) – for liquids liters (l) – for liquids fluid ounces (fl oz) – for liquids gallons (gal) – for liquids Select the unit of weight for the second product.

Results

per standardized unit
Calculated as: (Price / Weight) * Conversion Factor
Price/Weight (Product 1)
Price/Weight (Product 2)
Difference
Results copied successfully!
Comparison Table
Product Price Weight Price Per Standard Unit
Product 1
Product 2
Price Per Weight Comparison Chart

What is a Price Per Weight Calculator App?

{primary_keyword} is a simple yet powerful tool designed to help consumers and businesses make more informed purchasing decisions. At its core, a price per weight calculator app allows you to compare the cost-effectiveness of different products based on how much they cost relative to their weight or volume. This is particularly useful when comparing items sold in different sizes or packaging, where the sticker price alone can be misleading. By standardizing the comparison to a common unit of weight (like grams, kilograms, ounces, or pounds) or volume (like milliliters, liters, fluid ounces, or gallons), you can accurately determine which product offers the best value for your money.

Who should use a price per weight calculator app?

  • Savvy Shoppers: Anyone looking to maximize their budget and get the most for their money, whether buying groceries, household supplies, or even bulk goods.
  • Small Business Owners: Procurement managers or small business owners who need to purchase inventory or supplies in bulk and want to ensure they are getting the best possible price.
  • Budget-Conscious Consumers: Individuals and families managing tight budgets who need to stretch their spending as far as possible.
  • Comparison Shoppers: People who frequently compare similar products from different brands or retailers.

Common Misconceptions:

  • It only applies to food: While very common in grocery shopping, price per weight is relevant for almost any item sold by weight or volume, from cleaning supplies and pet food to industrial materials and raw ingredients.
  • The cheapest option is always best: A price per weight calculator highlights the best *value*, not necessarily the lowest *total cost*. A larger package might have a lower price per weight but a higher overall price, which might not be suitable for everyone's immediate needs or budget.
  • Unit conversion is too complex: Modern price per weight calculator apps handle unit conversions automatically, taking the guesswork out of comparing items measured in different units (e.g., comparing a product sold in grams to one sold in pounds).

Price Per Weight Calculator App Formula and Mathematical Explanation

The fundamental principle behind a price per weight calculator app is to determine the cost of a product per a standardized unit of measurement. This allows for an apples-to-apples comparison, regardless of package size or the units used by the manufacturer.

The core calculation involves dividing the total price of a product by its total weight or volume. To compare products that might use different units (e.g., one product in grams and another in pounds), a conversion factor is applied to standardize them to a common unit.

The Formula:

Price Per Standard Unit = (Price / Weight) * Conversion Factor

Where:

  • Price: The total cost of the product.
  • Weight: The total weight or volume of the product as stated by the manufacturer.
  • Conversion Factor: A multiplier used to convert the product's original weight/volume unit to a chosen standard unit (e.g., grams, kilograms, ounces, pounds, liters, gallons).

For instance, if we want to compare two products and standardize to grams:

  1. Calculate Price per Unit for Product 1: \( PPW_1 = \frac{\text{Price}_1}{\text{Weight}_1} \) (in its original unit)
  2. Convert to Standard Unit for Product 1: If Product 1 is in kg and standard is grams, \( \text{Standard Price/Weight}_1 = PPW_1 \times 1000 \text{ g/kg} \)
  3. Calculate Price per Unit for Product 2: \( PPW_2 = \frac{\text{Price}_2}{\text{Weight}_2} \) (in its original unit)
  4. Convert to Standard Unit for Product 2: If Product 2 is in lb and standard is grams, \( \text{Standard Price/Weight}_2 = PPW_2 \times 453.592 \text{ g/lb} \)

The product with the lower "Standard Price/Weight" is the better value.

Variable Explanations

Let's break down the key variables involved:

Variables Used in Price Per Weight Calculation
Variable Meaning Unit Typical Range
Price The total cost paid for the product. Currency (e.g., USD, EUR, GBP) $0.10 – $1000+ (depends on product)
Weight/Volume The net weight or volume of the product. g, kg, oz, lb, ml, l, fl oz, gal 0.1 – 1000+ (depends on product size)
Unit of Measurement The specific unit used to quantify the product's weight or volume. g, kg, oz, lb, ml, l, fl oz, gal N/A (Categorical)
Standard Unit The common unit to which all products are converted for comparison. g, kg, oz, lb, ml, l, fl oz, gal N/A (Selected by user/calculator)
Price Per Standard Unit The calculated cost for one unit of the standardized measurement. This is the key metric for comparison. Currency / Standard Unit (e.g., $/g, $/kg, $/oz) $0.001 – $100+ (depends on product and unit)
Conversion Factor The multiplier needed to convert the product's original unit to the standard unit. Unitless ratio (e.g., 1000 g/kg) Varies based on units being converted

Practical Examples (Real-World Use Cases)

Understanding the application of the {primary_keyword} is best done through examples:

Example 1: Comparing Cereals

Sarah is at the grocery store trying to decide between two boxes of her favorite cereal:

  • Product A: 375g box for $4.50
  • Product B: 500g box for $5.75

Sarah wants to find out which cereal offers better value. She uses the price per weight calculator app, standardizing to grams (g).

Inputs:

  • Product 1: Price = $4.50, Weight = 375 g, Unit = g
  • Product 2: Price = $5.75, Weight = 500 g, Unit = g

Calculation:

  • Product A Price/Weight: $4.50 / 375 g = $0.012 per gram
  • Product B Price/Weight: $5.75 / 500 g = $0.0115 per gram

Result: Product B has a lower price per gram ($0.0115/g) compared to Product A ($0.012/g). Even though Product B is more expensive overall, it offers better value for money.

Financial Interpretation: Sarah should buy Product B if she plans to consume the entire amount or store it, as she will save money in the long run compared to buying Product A repeatedly.

Example 2: Comparing Cleaning Supplies

Mark needs to buy laundry detergent. He finds two options:

  • Product X: A 1.5-liter bottle for $8.99
  • Product Y: A 64-fluid ounce bottle for $10.49

Mark knows that liquids are often measured differently and wants to compare them accurately. He uses the calculator, choosing to standardize to fluid ounces (fl oz).

Inputs:

  • Product X: Price = $8.99, Volume = 1.5 L, Unit = l
  • Product Y: Price = $10.49, Volume = 64 fl oz, Unit = fl oz

Conversion: 1 liter ≈ 33.814 fluid ounces

Calculation:

  • Product X Volume in fl oz: 1.5 L * 33.814 fl oz/L ≈ 50.72 fl oz
  • Product X Price/Volume: $8.99 / 50.72 fl oz ≈ $0.1772 per fl oz
  • Product Y Price/Volume: $10.49 / 64 fl oz ≈ $0.1639 per fl oz

Result: Product Y has a lower price per fluid ounce ($0.1639/fl oz) compared to Product X ($0.1772/fl oz).

Financial Interpretation: Mark gets more detergent for his money by purchasing Product Y, despite its higher initial cost. This knowledge helps him make a sound financial decision for his household budget.

How to Use This Price Per Weight Calculator App

Using the {primary_keyword} is straightforward. Follow these simple steps:

  1. Enter Product 1 Details: Input the total Price of the first product and its total Weight (or volume). Then, select the correct Weight Unit from the dropdown menu (e.g., grams, kg, oz, lb, ml, l, fl oz, gal).
  2. Enter Product 2 Details: Repeat the process for the second product, entering its Price, Weight, and selecting its Weight Unit.
  3. Calculate: Click the "Calculate" button.

How to Read Results:

  • Main Result: The calculator will display the price per a standardized unit (e.g., per gram, per ounce) for both products, highlighting the lower value. This is the primary indicator of which product offers better value.
  • Intermediate Results: You'll see the calculated price per unit for each individual product and the absolute difference between them. This provides a clearer picture of the savings.
  • Comparison Table: A table summarizes the key figures for easy viewing.
  • Chart: A visual representation compares the price per unit for both products, making the value difference immediately apparent.

Decision-Making Guidance:

The product with the lower "Price Per Standard Unit" is the more economical choice. Consider the following when making your final decision:

  • Budget: While a lower price per unit is better value, ensure the total price of the larger/more economical option fits your immediate budget.
  • Consumption Rate: If you use a product quickly, buying in larger quantities with a lower price per unit makes sense. If you use it slowly, a smaller, cheaper option might be better to avoid spoilage or waste.
  • Storage Space: Do you have adequate space to store larger bulk purchases?
  • Promotions: Always check for current sales or loyalty program benefits that might further influence your decision.

Key Factors That Affect Price Per Weight Results

While the price per weight calculation provides a clear quantitative comparison, several factors can influence the perceived or actual value:

  1. Unit Consistency: The most crucial factor. Inaccurate unit selection or conversion can lead to fundamentally flawed comparisons. Always double-check units used by manufacturers and the calculator.
  2. Product Quality & Features: A lower price per weight doesn't always mean better overall value if the quality, effectiveness, or features of the product are significantly inferior. For instance, a cheaper detergent might require more to achieve the same cleaning power.
  3. Brand Perception & Loyalty: Some consumers may prioritize a trusted brand name or specific product attributes over the absolute lowest price per weight. This is a subjective factor often influencing purchasing decisions beyond pure economics.
  4. Promotional Pricing & Discounts: Temporary sales, buy-one-get-one offers, or coupons can skew the perceived value. The calculator typically uses the listed price, so it's essential to factor in current deals. A product with a higher base price per weight might be cheaper during a sale.
  5. Packaging & Presentation: While the calculator focuses on the product's content, packaging can sometimes influence perceived value. Premium packaging might justify a slightly higher price for some consumers, even if the price per weight is less favorable.
  6. Bulk Purchase Economies of Scale: Larger packages often benefit from reduced manufacturing and packaging costs per unit, leading to lower price per weight. This is the fundamental principle the calculator leverages.
  7. Expiration Dates & Shelf Life: For perishable goods, a product with a longer shelf life or a later expiration date might offer better value even if its initial price per weight is slightly higher, as it reduces the risk of waste.
  8. Usage Efficiency: Some products are more concentrated or efficient than others. For example, a concentrated cleaner might have a higher price per volume but require less product per use, ultimately offering better value. The calculator typically uses the stated volume/weight, not necessarily the "active" ingredient amount.

Frequently Asked Questions (FAQ)

Q: Can I compare products measured in different units (e.g., grams vs. ounces)?

A: Yes! The price per weight calculator app is designed specifically for this. Simply select the correct unit of measurement for each product, and the calculator will handle the conversion to provide a standardized comparison.

Q: What's the difference between price per weight and just looking at the total price?

A: The total price only tells you how much you pay upfront. Price per weight tells you the value you're getting relative to the quantity. A larger package might cost more initially but offer better value per unit of weight or volume.

Q: Is a lower price per weight always the best choice?

A: Not necessarily. While it indicates better value for money, consider factors like your budget, how quickly you'll use the product, storage space, and quality preferences.

Q: How accurate are the unit conversions?

A: The calculator uses standard, widely accepted conversion factors. For most common goods, these are highly accurate. Be aware that specific industries might have niche standards, but for general consumer goods, it's reliable.

Q: Can I use this calculator for non-food items?

A: Absolutely. Any item sold by weight or volume – such as cleaning supplies, pet food, hardware, raw materials, or personal care products – can be effectively compared using a price per weight calculation.

Q: What does the "Difference" result mean?

A: The "Difference" result shows the absolute monetary saving per standardized unit if you choose the more economical option. For example, if the difference is $0.005, it means you save half a cent for every gram (or your chosen standard unit) by buying the better-value product.

Q: My calculator shows "Infinity" or "NaN" as a result. What's wrong?

A: This usually happens if you enter a weight or volume of zero for one of the products. Division by zero is mathematically undefined. Please ensure all weight/volume inputs are positive numbers.

Q: How does this relate to unit pricing on store shelves?

A: This calculator essentially automates and standardizes the unit pricing you might see in stores. It allows you to perform these comparisons yourself, even when stores don't clearly display unit prices or use inconsistent units.
var price1Input = document.getElementById("price1"); var weight1Input = document.getElementById("weight1"); var weightUnit1Select = document.getElementById("weightUnit1"); var price2Input = document.getElementById("price2"); var weight2Input = document.getElementById("weight2"); var weightUnit2Select = document.getElementById("weightUnit2"); var price1Error = document.getElementById("price1Error"); var weight1Error = document.getElementById("weight1Error"); var price2Error = document.getElementById("price2Error"); var weight2Error = document.getElementById("weight2Error"); var mainResultDiv = document.getElementById("mainResult"); var ppw1Span = document.getElementById("ppw1"); var ppw2Span = document.getElementById("ppw2"); var differenceSpan = document.getElementById("difference"); var tablePrice1 = document.getElementById("tablePrice1"); var tableWeight1 = document.getElementById("tableWeight1"); var tablePPW1 = document.getElementById("tablePPW1"); var tablePrice2 = document.getElementById("tablePrice2"); var tableWeight2 = document.getElementById("tableWeight2"); var tablePPW2 = document.getElementById("tablePPW2"); var copyMessage = document.getElementById("copyMessage"); var chart; var chartCtx; var standardUnit = 'g'; // Default standard unit var unitConversionFactors = { 'g': 1, 'kg': 1000, 'oz': 28.3495, 'lb': 453.592, 'ml': 1, // For liquids, assume density is close to 1g/ml or use as volume unit 'l': 1000, 'fl oz': 29.5735, 'gal': 3785.41 }; function getStandardUnit() { // Prioritize common units for display, but calculation uses 'g' internally for consistency // For this specific app, we'll standardize to grams for weight and ml for liquids if mixed var unit1 = weightUnit1Select.value; var unit2 = weightUnit2Select.value; if ((unit1.includes('g') || unit1.includes('kg') || unit1.includes('oz') || unit1.includes('lb')) && (unit2.includes('g') || unit2.includes('kg') || unit2.includes('oz') || unit2.includes('lb'))) { return 'g'; // Standardize to grams if both are weight units } else if ((unit1.includes('ml') || unit1.includes('l') || unit1.includes('fl oz') || unit1.includes('gal')) && (unit2.includes('ml') || unit2.includes('l') || unit2.includes('fl oz') || unit2.includes('gal'))) { return 'ml'; // Standardize to milliliters if both are liquid units } else { // If mixing weight and liquid, use grams as a common ground if possible or default return 'g'; } } function convertToStandardUnit(value, unit) { var standard = getStandardUnit(); if (!unitConversionFactors.hasOwnProperty(unit) || !unitConversionFactors.hasOwnProperty(standard)) { console.error("Invalid unit for conversion:", unit, standard); return NaN; } var factor = unitConversionFactors[unit]; var standardFactor = unitConversionFactors[standard]; if (isNaN(factor) || isNaN(standardFactor) || factor === 0 || standardFactor === 0) { console.error("Zero or NaN conversion factor detected for:", unit, standard); return NaN; } // Convert original value to grams/ml, then to the standard unit var valueInGramsOrMl = value * factor; return valueInGramsOrMl / standardFactor; } function formatCurrency(amount) { if (isNaN(amount) || amount === null) return '–'; return amount.toLocaleString(undefined, { style: 'currency', currency: 'USD' }); // Defaulting to USD, can be made dynamic } function formatValue(value, unit) { if (isNaN(value) || value === null) return '–'; var formatted = value.toFixed(5); // High precision for comparison return formatted + ' / ' + unit; } function calculatePricePerWeight() { var price1 = parseFloat(price1Input.value); var weight1 = parseFloat(weight1Input.value); var unit1 = weightUnit1Select.value; var price2 = parseFloat(price2Input.value); var weight2 = parseFloat(weight2Input.value); var unit2 = weightUnit2Select.value; var isValid = true; // Clear previous errors price1Error.style.display = 'none'; weight1Error.style.display = 'none'; price2Error.style.display = 'none'; weight2Error.style.display = 'none'; // Validate inputs if (isNaN(price1) || price1 < 0) { price1Error.textContent = "Please enter a valid price (0 or greater)."; price1Error.style.display = 'block'; isValid = false; } if (isNaN(weight1) || weight1 <= 0) { weight1Error.textContent = "Please enter a valid weight (greater than 0)."; weight1Error.style.display = 'block'; isValid = false; } if (isNaN(price2) || price2 < 0) { price2Error.textContent = "Please enter a valid price (0 or greater)."; price2Error.style.display = 'block'; isValid = false; } if (isNaN(weight2) || weight2 <= 0) { weight2Error.textContent = "Please enter a valid weight (greater than 0)."; weight2Error.style.display = 'block'; isValid = false; } if (!isValid) { resetResults(); return; } standardUnit = getStandardUnit(); // Determine the unit for comparison var standardUnitDisplay = standardUnit; // e.g., 'g' or 'ml' var ppw1_raw = price1 / weight1; // Price per original unit var ppw2_raw = price2 / weight2; // Price per original unit var convertedWeight1 = convertToStandardUnit(weight1, unit1); var convertedWeight2 = convertToStandardUnit(weight2, unit2); if (isNaN(convertedWeight1) || isNaN(convertedWeight2)) { console.error("Conversion failed for one or both products."); resetResults(); return; } var ppw1_standard = price1 / convertedWeight1; var ppw2_standard = price2 / convertedWeight2; var difference = Math.abs(ppw1_standard – ppw2_standard); var betterValueProduct = (ppw1_standard < ppw2_standard) ? 1 : 2; // Display results mainResultDiv.textContent = formatCurrency(Math.min(ppw1_standard, ppw2_standard)); document.querySelector('.main-result-unit').textContent = 'per ' + standardUnitDisplay; ppw1Span.textContent = formatValue(ppw1_standard, standardUnitDisplay); document.querySelectorAll('#results .intermediate-results div')[0].querySelector('.unit').textContent = standardUnitDisplay; ppw2Span.textContent = formatValue(ppw2_standard, standardUnitDisplay); document.querySelectorAll('#results .intermediate-results div')[1].querySelector('.unit').textContent = standardUnitDisplay; differenceSpan.textContent = formatCurrency(difference); document.querySelectorAll('#results .intermediate-results div')[2].querySelector('.unit').textContent = standardUnitDisplay; // Update table tablePrice1.textContent = formatCurrency(price1); tableWeight1.textContent = weight1 + ' ' + unit1; tablePPW1.textContent = formatValue(ppw1_standard, standardUnitDisplay); tablePrice2.textContent = formatCurrency(price2); tableWeight2.textContent = weight2 + ' ' + unit2; tablePPW2.textContent = formatValue(ppw2_standard, standardUnitDisplay); // Update Chart updateChart(ppw1_standard, ppw2_standard, standardUnitDisplay); } function resetResults() { mainResultDiv.textContent = '–'; ppw1Span.textContent = '–'; ppw2Span.textContent = '–'; differenceSpan.textContent = '–'; document.querySelector('.main-result-unit').textContent = 'per standardized unit'; tablePrice1.textContent = '–'; tableWeight1.textContent = '–'; tablePPW1.textContent = '–'; tablePrice2.textContent = '–'; tableWeight2.textContent = '–'; tablePPW2.textContent = '–'; if (chart) { chart.destroy(); chart = null; } copyMessage.style.display = 'none'; } function resetCalculator() { price1Input.value = ""; weight1Input.value = ""; weightUnit1Select.value = "g"; price2Input.value = ""; weight2Input.value = ""; weightUnit2Select.value = "g"; // Clear errors price1Error.style.display = 'none'; weight1Error.style.display = 'none'; price2Error.style.display = 'none'; weight2Error.style.display = 'none'; resetResults(); } function copyResults() { var resultText = "Price Per Weight Comparison:\n\n"; resultText += "Product 1:\n"; resultText += " Price: " + tablePrice1.textContent + "\n"; resultText += " Weight: " + tableWeight1.textContent + "\n"; resultText += " Price/Unit: " + tablePPW1.textContent + "\n\n"; resultText += "Product 2:\n"; resultText += " Price: " + tablePrice2.textContent + "\n"; resultText += " Weight: " + tableWeight2.textContent + "\n"; resultText += " Price/Unit: " + tablePPW2.textContent + "\n\n"; resultText += "Key Result:\n"; resultText += " Best Value Price: " + mainResultDiv.textContent + " " + document.querySelector('.main-result-unit').textContent + "\n"; resultText += " Difference: " + differenceSpan.textContent + " per " + document.querySelector('.main-result-unit').textContent.replace('per ', '') + "\n"; resultText += "\nFormula Used: Price / Weight (standardized to " + standardUnit + ")"; var textArea = document.createElement("textarea"); textArea.value = resultText; document.body.appendChild(textArea); textArea.select(); try { document.execCommand("copy"); copyMessage.textContent = "Results copied successfully!"; copyMessage.style.display = 'block'; setTimeout(function() { copyMessage.style.display = 'none'; }, 3000); } catch (err) { copyMessage.textContent = "Failed to copy. Please copy manually."; copyMessage.style.display = 'block'; console.error("Copy failed: ", err); } document.body.removeChild(textArea); } function initializeChart() { chartCtx = document.getElementById("priceWeightChart").getContext("2d"); // Chart will be created/updated in updateChart } function updateChart(ppw1, ppw2, unit) { if (!chartCtx) { initializeChart(); } if (chart) { chart.destroy(); // Destroy previous chart instance } var product1Label = "Product 1"; var product2Label = "Product 2"; var data = { labels: [product1Label, product2Label], datasets: [{ label: 'Price Per ' + unit.toUpperCase(), data: [ppw1, ppw2], backgroundColor: [ 'rgba(0, 74, 153, 0.6)', // Primary color 'rgba(40, 167, 69, 0.6)' // Success color ], borderColor: [ 'rgba(0, 74, 153, 1)', 'rgba(40, 167, 69, 1)' ], borderWidth: 1 }] }; chart = new Chart(chartCtx, { type: 'bar', // or 'pie' or 'doughnut' data: data, options: { responsive: true, maintainAspectRatio: true, // Ensure it respects container size scales: { y: { beginAtZero: true, title: { display: true, text: 'Price per Standard Unit' } } }, plugins: { legend: { display: true, position: 'top', }, title: { display: true, text: 'Price Per Unit Comparison' } } } }); } // Initial setup when the page loads document.addEventListener("DOMContentLoaded", function() { initializeChart(); // Initialize canvas context // Optionally call calculatePricePerWeight() with default values if needed // Or just wait for user input });

Leave a Comment