Crypto Profit Calculator: Net Profit, ROI, and Break-Even on a Trade

Most people figure out a crypto trade with a quick subtraction: sold for more than I paid, so I made money. That number is almost always wrong, and it is wrong in a predictable direction. It is too high, because it ignores the fee on the way in, the fee on the way out, and the fact that your "return" should be measured against the cash you actually committed, not the headline price. A crypto profit calculator closes that gap so the figure you log matches the figure your exchange settled.

This post walks through the math a profit-and-loss calculation should do, runs one full example end to end, and explains the one line that matters most when you still hold the position: the break-even sell price.

The four numbers a trade actually produces

A single buy-and-sell round trip generates more than one answer, and confusing them is where mistakes start. There are four worth separating:

• Net profit — the dollars left after both fees, in your pocket.
• Return percentage (ROI) — net profit as a share of what you committed.
• Raw price move — how far the coin's price travelled, before any costs.
• Break-even sell price — the price you must sell at just to come out even.

The raw price move is the easy one and the least useful. If a coin goes from 30,000 to 35,000 it moved about 16.7%. But you never earned 16.7%, because two fees came out of that move and the buy-side fee inflated your real cost. The ROI line is the one that answers "what did this actually return?"

The formulas, written out

Here is the arithmetic with nothing hidden. Let amount be the quantity of coins, and express each fee as a percent of that leg.

cost        = buy price × amount
buy fee     = cost × (buy fee% ÷ 100)
committed   = cost + buy fee

gross       = sell price × amount
sell fee    = gross × (sell fee% ÷ 100)
proceeds    = gross − sell fee

profit      = proceeds − committed
           = (sell price − buy price) × amount − fees
return%     = profit ÷ committed × 100

The simplest way to remember net profit is the second line: profit = (sell price − buy price) × amount − fees. The price spread times your quantity is the gross gain, and the two fees are the only thing standing between it and your wallet.

Break-even gets its own formula because it answers a forward-looking question — not "what did I make?" but "what do I need?":

break-even sell price = buy price × (1 + buy fee%/100) ÷ (1 − sell fee%/100)

Notice it sits above your buy price. Selling at exactly what you paid still loses money, because the sell-side fee was never recovered. The break-even price is the floor that makes the whole round trip add up to zero.

A worked example: 0.5 of a coin, 30,000 to 35,000

Say you bought 0.5 of a coin at 30,000 and later sold the same 0.5 at 35,000. Your exchange charges a 0.1% fee on each side. Plug those into the formulas:

• Cost: 30,000 × 0.5 = 15,000
• Buy fee: 15,000 × 0.001 = 15
• Committed: 15,000 + 15 = 15,015
• Gross proceeds: 35,000 × 0.5 = 17,500
• Sell fee: 17,500 × 0.001 = 17.50
• Net proceeds: 17,500 − 17.50 = 17,482.50
• Net profit: 17,482.50 − 15,015 = 2,467.50
• ROI: 2,467.50 ÷ 15,015 × 100 ≈ 16.43%

Now compare that 16.43% ROI to the raw price move of 16.67%. The gap — about a quarter of a percent — is the round-trip fee of 32.50 chewing into your gain. On a small move that gap can be the difference between green and red, which is exactly why the fee line is not optional.

And the break-even? With a 30,000 buy and 0.1% on each side:

30,000 × 1.001 ÷ 0.999 ≈ 30,060.06

So you needed to sell above roughly 30,060 just to avoid a loss. Selling at 30,000 flat would have cost you about 30 — the two fees you never earned back.

Why I built the fee fields to take percent, not decimals

When I was testing this, the single most common slip I made myself was typing the fee as a decimal — 0.001 instead of 0.1 for a 0.1% maker fee. That one keystroke understates your fees by a factor of a hundred and quietly inflates the profit, and because the output still looks plausible you don't catch it. I settled on percent-style inputs precisely because that is how exchanges print their fee schedules: a tier says "0.10% taker," so you type 0.1. Match the tool's input to the number already on your screen and the whole class of mistake disappears.

The other habit worth building: read the ROI line, never the price-change line, when you want to know what you earned. The price change is a fact about the market. The ROI is a fact about your money.

Quantity mode and amount-invested mode

There are two honest ways to describe the same position. Sometimes you know the coin count — you bought 0.5 of a coin, or 1,200 of a smaller one. Sometimes you only know the cash — you put in exactly 500 and never tracked the precise amount. Both lead to the same profit math; the only difference is how the quantity is supplied. In amount mode the tool derives the coin count as amount ÷ buy price, then runs everything else identically. Dollar-cost figures are far easier to enter that way than to convert by hand.

If you want to compare a crypto position against a non-crypto one on the same percentage basis, the plain ROI calculator uses the identical "profit over committed capital" definition, so the two numbers are directly comparable.

This is arithmetic, not financial advice

One thing to be clear about: a profit calculator does arithmetic on numbers you type, and nothing more. It does not know about tax lots, holding-period rules, wash sales, slippage, the spread you actually filled at, or funding rates on a leveraged position. It is not a recommendation to buy, sell, or hold anything, and a clean-looking ROI is not a signal. For tax reporting, use the cost basis and proceeds your exchange documents and talk to a professional. Treat the output here as a sharper version of the back-of-envelope math you were already doing — accurate about fees and returns, silent about whether the trade was a good idea.

That is the right division of labor. The tool gets the number right; the judgment stays with you.

---

Made by Toolora · Updated 2026-06-13