This guide explains how to use the calculator. It is not tax advice — all outputs are estimates for planning purposes only. See our Disclaimer for full details.
Every number you enter is processed entirely in your browser using JavaScript. Nothing is sent to a server, saved, or transmitted. If you close the tab, it's gone. You can verify this yourself by opening your browser's network tab while using the calculator — no outbound data requests are made.
The calculator does not auto-detect your location — you must manually select USA or UK. If you're in another country, the estimates won't reflect your local tax law. The tool is built specifically for US and UK tax rules only.
| Field | What to enter | Example |
|---|---|---|
| Purchase Price | The price you paid per unit when you bought | $20,000 |
| Selling Price | The current price (or the price you plan to sell at) per unit | $65,000 |
| Amount Held | How many units you hold (decimals are fine) | 1.5 |
Since the calculator updates in real time as you type, you can test multiple selling prices without resetting anything — just change the Selling Price field and the results update instantly. This is useful for modelling "what if I sell at $50k vs $70k vs $100k" without needing to refresh the page.
In reality, staking rewards are taxed at their fair market value on the date each reward was received — not at today's selling price. If you received rewards across many dates at different prices, this field gives you a directional estimate only. For accurate staking income reporting, you need a record of each reward's value on its specific receipt date. See our Crypto Staking Tax Guide for the full explanation.
| Region | Options Available | How to choose |
|---|---|---|
| 🇺🇸 USA | Preset buttons (10%, 20%, 30%, 40%) + custom slider (0–40%) | Use your actual marginal income tax rate for short-term gains, or your long-term CGT rate (0%, 15%, or 20%) for assets held over 12 months |
| 🇬🇧 UK | Two fixed buttons only: 18% (Basic Rate) or 24% (Higher Rate) | Choose based on your income tax band — Basic Rate if your total income is under £50,270, Higher Rate if above |
HMRC's Capital Gains Tax for individuals has exactly two rates — 18% or 24%. There is no valid in-between rate for a UK individual. Allowing a custom slider would let users generate a tax figure that cannot exist under real UK tax law, so we removed it in UK mode deliberately.
If you've held your asset for more than 12 months use your long-term rate (0%, 15%, or 20% depending on your income). If 12 months or less, use your ordinary income tax rate. The difference can be significant — see our Crypto Capital Gains Tax Guide for a worked example.
The badge in the top right of the results panel shows GAIN (green) or LOSS (red) based on whether your gross gain is positive or negative. A loss result means the selling price you entered is below your purchase price — no tax is owed on a loss, and it may be usable to offset other gains.