What gains.tax is and what it never does
This page is a stub. The full guide is written against the shipped app version and is on its way.
gains.tax is a UK crypto tax calculator that runs entirely in your browser. You open the app, you bring your transaction history to it, and every calculation happens on your machine. There is no server holding a copy of your financial life, because nothing is ever sent to one. You can verify this yourself, open the browser’s network panel while you work and watch the silence.
What it does. Imports your history from exchange exports and other tax tools, reconciles it with the row count shown on screen, applies the UK matching rules, section 104 pooling, same-day matching, and the 30-day rule, and produces reports where every disposal names the rule and the legislation behind it. The rules themselves are published with their proofs on the verification page.
What it never does, the standing list.
Never uploads your data. The optional exceptions, wallet scanning, price lookups, and exchange sync, are visible before they happen and explained in the privacy model.
Never requires a signup. There is no account, no password, and no profile.
Never charges per tax year. The app is free up to 1,000 transactions, reports included. Past that, one payment covers every tax year you have ever had and every one still to come.
Never holds your data hostage. Your session file exports at any size, paid or not, always.
What it costs. Nothing up to 1,000 transactions. Above that, report downloads ask for a licence key, priced on the pricing page, one payment, no subscription. Everything else keeps working without one, importing, reconciling, the dashboard, and the session export.