Crypto ROI Calculator

Computes return on investment for a cryptocurrency position given entry price, exit price, position size, and fees. Outputs absolute profit, percentage return, and annualized return where a holding period is supplied.

Fees may include trading fees on both sides, network gas costs, and a slippage allowance. Tax is excluded; jurisdictional treatment of crypto disposals varies widely and is left to the user.

The calculation follows the standard ROI formula: (proceeds − cost basis) / cost basis. Cost basis includes entry price multiplied by quantity plus buy-side fees. Proceeds equal exit price multiplied by quantity minus sell-side fees. Annualized return uses the compound formula: (1 + total return)^(365/days held) − 1, which converts a holding-period return into an equivalent yearly compounding rate.

A worked example: 0.5 BTC purchased at $42,000 with a 0.5% exchange fee, sold 90 days later at $58,000 with the same fee. Cost basis = $21,000 + $105 = $21,105. Proceeds = $29,000 − $145 = $28,855. Profit = $7,750. Total return = 36.7%. Annualized = (1.367)^(365/90) − 1 = 391%. The annualized figure dramatizes the short-term gain; a 36.7% return over three months sustained for a full year would compound to nearly five-fold, which is why short-term annualization is a useful but easily abused metric.

The fee structure on real platforms often differs from a single percentage. Maker/taker spreads charge less for limit orders (maker) than market orders (taker). DEX swaps incur LP fees (typically 0.3% on Uniswap v2-style pools) plus network gas, which can dominate small trades on Ethereum mainnet. Slippage on large orders against thin liquidity is sometimes the largest cost; a 1% slippage on a $100,000 order is $1,000, often exceeding the trading fee.

Limitations: the calculator handles a single round-trip position. Real portfolios have multiple lots with different cost bases, partial sells, transfers between wallets, and yield from staking or LP positions. Tax accounting (FIFO, LIFO, specific identification) further complicates the picture. For tax purposes, dedicated crypto accounting software (Koinly, CoinTracker) is needed; the calculator is suitable for forward-looking scenario analysis or single-position back-tests, not for filing.