Supported formats, everything the app can read

Checked against app build 2026-08-26-01-41 on 2026-08-26.

Five ways in, every one of them ending at the same preview-and-reconcile step, nothing joins the workspace unseen.

Which files can gains.tax read?

Tax tool exports, exchange statements, and any plain CSV that carries dates, assets, amounts and directions.

Tax tool exports. Koinly, both of its export shapes including the full account export, CoinLedger, CoinTracking and CoinTracker, each mirrored one to one against the source’s format.

Exchange statements. Coinbase, Kraken and Binance statement files import directly, no tax tool in between.

Any plain CSV. A file with dates, assets, amounts and directions can be read even when it matches no known vendor shape. Ambiguities queue in Reconcile rather than being guessed.

What about awkward or foreign file shapes?

They parse, and the ones too broken to parse are refused out loud rather than dropped.

European exports with semicolon delimiters and comma decimals read correctly, the parser keys the number format to the file’s own delimiter. UTF-16 files, byte-order marks, Windows line endings, quoted thousands, scientific notation for dust quantities, dotted European dates, currency symbols, epoch timestamps and duplicate mid-file headers all parse. Rows too broken to use are refused with a reason naming what is missing, never dropped without a word, see error messages, and eighteen torture cases pin all of this permanently in the test suite.

Can it read my history without a file at all?

Yes, two ways, on-chain scanning and live exchange sync.

On-chain scanning. Bitcoin plus six EVM chains, Ethereum, Arbitrum, Base, Gnosis, Optimism and Polygon, from public explorers, covered in wallet scanning.

Live exchange sync. Kraken and Binance with read-only API keys, signed in your browser, through the relay.

What formats does the app write back out?

The session file, which is the whole workspace, plus the report family.

The session file exports the whole workspace at any size, free, always, and reopens in the app on any machine, it is also the format for sharing with your accountant. Reports export per the downloads guide.

Missing a source you need? Say so at [email protected], the import roadmap is built from exactly those messages.