How a crypto conversion rate is calculated
Converting crypto to fiat is a single multiplication: the quantity you hold multiplied by the price of one unit. Converting one crypto asset into another needs a cross rate, which is simply both assets priced in the same currency and then divided. If ETH trades at 3,200 and BTC at 64,000, one ETH is worth 3,200 / 64,000 = 0.05 BTC.
The arithmetic is trivial. What trips people up is that there is no single price. Every exchange has its own order book, its own liquidity and its own set of participants, so the same asset can be quoted a few basis points — occasionally a few percent — apart at the same instant. Aggregators publish a volume-weighted average, which matches no individual venue exactly.
A conversion rate is a snapshot, not a guaranteed execution price. It tells you what the market looked like a moment ago. What you actually receive depends on which side of the spread you cross, how deep the book is at your size, and how much the price moves between clicking and settling.
Worked example
Converting 0.75 ETH, with ETH quoted at 3,200 and BTC at 64,000, shown both into fiat and across into BTC.
| Input | Value |
|---|
| Quantity | 0.75 ETH |
| ETH price | 3,200 |
| Fiat value | 2,400 |
| BTC price | 64,000 |
| Cross rate (1 ETH in BTC) | 0.05 |
| Equivalent in BTC | 0.0375 |
Now add a realistic spread — a bid of 3,196 against an ask of 3,204. That gap is 0.25% of the mid price, and you pay it whenever you cross it. Convert 0.75 ETH out and straight back at those quotes and you end up with about 0.7481 ETH: the price never moved, but the round trip still cost you.
How to use this calculator
- Enter the quantity you actually hold, not a rounded approximation.
- Enter the current price for one unit — check it against the exchange you would actually trade on, not a headline figure.
- For a crypto-to-crypto conversion, enter both prices in the same currency so the cross rate is consistent.
- Compare the result against the bid or ask you are quoted, and treat the difference as a cost.
- Re-check the rate immediately before executing — a quote from ten minutes ago is not the price you will get.
Frequently asked questions
Why does the same coin show a different price on every exchange?
Each exchange is a separate market with its own order book and its own buyers and sellers. Prices stay broadly aligned because arbitrageurs profit from closing gaps, but liquidity, fees, regional demand and withdrawal frictions keep small differences alive continuously.
What is the spread and why does it matter?
The spread is the gap between the highest bid and the lowest ask. You buy at the ask and sell at the bid, so you cross it on every trade. It is a real cost that never appears on a fee schedule, and it widens on illiquid pairs and during volatility.
Will I get exactly the rate shown here?
No — treat it as an estimate. The rate you receive depends on the spread, the depth of the order book at your trade size, exchange fees, and how far the price moves between quote and fill. Large orders often fill at progressively worse prices as they consume the book.
Is it cheaper to convert directly or route through a major pair?
It depends entirely on liquidity. A thin direct pair can cost more in spread than two trades through a deep pair such as BTC or a major stablecoin — but routing means two spreads and two fees. Compare the all-in cost rather than assuming either route is better.
Does converting crypto to crypto trigger tax?
In many jurisdictions a crypto-to-crypto swap is treated as a disposal of the asset you gave up, even though no fiat was involved. Rules differ significantly by country and change over time, so confirm the current position where you are resident.
Why do stablecoins not always convert at exactly 1.00?
A stablecoin is pegged, not fixed. Its market price is set by supply and demand on exchanges and can trade slightly above or below the peg, occasionally by a wide margin under stress. Use the live quote rather than assuming parity.
This calculator is an educational tool. Results are estimates based on the inputs you provide and do not constitute financial advice. Verify figures with your bank, broker or a qualified advisor before acting on them.