function calculateCryptoGains() {
var buyPrice = parseFloat(document.getElementById('purchasePrice').value);
var sellPrice = parseFloat(document.getElementById('sellingPrice').value);
var quantity = parseFloat(document.getElementById('coinQuantity').value);
var buyFeePct = parseFloat(document.getElementById('buyFee').value) / 100;
var sellFeePct = parseFloat(document.getElementById('sellFee').value) / 100;
var currency = document.getElementById('currencySymbol').value;
if (isNaN(buyPrice) || isNaN(sellPrice) || isNaN(quantity)) {
alert("Please enter valid numerical values.");
return;
}
var initialValue = buyPrice * quantity;
var buyFeeAmount = initialValue * buyFeePct;
var totalCost = initialValue + buyFeeAmount;
var grossSaleValue = sellPrice * quantity;
var sellFeeAmount = grossSaleValue * sellFeePct;
var netSaleValue = grossSaleValue – sellFeeAmount;
var netProfit = netSaleValue – totalCost;
var roi = (netProfit / totalCost) * 100;
var totalFees = buyFeeAmount + sellFeeAmount;
document.getElementById('totalCostDisplay').innerText = currency + totalCost.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('totalSaleDisplay').innerText = currency + grossSaleValue.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('totalFeesDisplay').innerText = currency + totalFees.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
var profitDisplay = document.getElementById('netProfitDisplay');
profitDisplay.innerText = (netProfit >= 0 ? '+' : ") + currency + netProfit.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
profitDisplay.style.color = netProfit >= 0 ? '#38a169' : '#e53e3e';
var roiDisplay = document.getElementById('roiDisplay');
roiDisplay.innerText = roi.toFixed(2) + '%';
roiDisplay.style.color = roi >= 0 ? '#38a169' : '#e53e3e';
document.getElementById('cryptoResults').style.display = 'block';
}
Understanding Your Crypto Gains
Calculating profits in the volatile world of cryptocurrency requires more than just looking at the price difference. To get an accurate picture of your investment performance, you must account for transaction fees and quantity precision.
Entry Price: The price per coin at the moment your order was executed.
Exchange Fees: Most platforms like Coinbase, Binance, or Kraken charge a percentage (typically 0.1% to 0.5%) for every trade. This "spread" or fee eats into your margins.
Return on Investment (ROI): This percentage shows the efficiency of your investment. A positive ROI indicates a gain, while a negative ROI indicates a loss relative to your total capital spent.
Realistic Calculation Example
Imagine you purchased 0.5 BTC when the price was 50,000. Your exchange charges a 0.1% fee.
Initial Investment: 0.5 * 50,000 = 25,000
Buy Fee: 25,000 * 0.001 = 25
Total Cost: 25,025
If you sell that 0.5 BTC later at 60,000:
Gross Sale: 0.5 * 60,000 = 30,000
Sell Fee: 30,000 * 0.001 = 30
Net Proceeds: 29,970
Your Net Profit would be 29,970 – 25,025 = 4,945, with an ROI of approximately 19.76%.
Tax Considerations
In many jurisdictions, cryptocurrency is treated as property. This means every time you trade one coin for another or sell for fiat, it may trigger a capital gains tax event. Keeping track of your cost basis (the total amount you paid including fees) is essential for accurate tax reporting.