See what your 1099-DA likely overstates. Free, 3 minutes, no card.
One box, any start: drop a CSV export, paste a wallet address, or type your exchange's name. Read-only data; you see what we found before you create an account or pay anything.
Read-only by design · no account needed yet · data deleted in 7 days if you don’t continue
Upload a CSV
A transaction-history export from your exchange — or your 1099-DA itself. We auto-detect 13 formats: Coinbase, Kraken, Binance, Crypto.com, KuCoin, Cash App, Revolut, Bitpanda, Nexo, plus Koinly / CoinTracker / CoinLedger / CoinTracking migration files and our universal template.
Templates: 1099-DA CSV · universal CSV
Several years of history in one file, or several files? Upload them all — the ledger is built once, whole, then split by year. Unfiled years, and what catching up costs (EN) →
Paste a wallet address live
Nineteen networks read now: Bitcoin — where an xpub, ypub or zpub reads the whole wallet rather than one address — plus Ethereum, Base, Optimism, Arbitrum One, Polygon, Gnosis Chain, Scroll, zkSync Era, Mode, Unichain, Ink, Lisk, Soneium, Shape, World Chain, Celo, Immutable zkEVM and Rootstock. Paste the address into the box above, pick the network, press Run. Every transfer, token movement and gas fee comes from the public chain — no API key, no connection, nothing you grant us and nothing we could lose. It is the same address block explorers already show the world.
Solana is not here, and we would rather say why than call it coming soon: the keyless endpoints we measured either index a couple of days of history or rate-limit transaction reads to about seven in ten, so a partial ledger would be the normal outcome — and a partial ledger that looks complete is worse than no import. Read-only exchange API connections come later, and withdrawal-enabled keys will be rejected automatically. Every exchange above already has a 30-second CSV path — type its name and we show the exact steps.
How address import works, and what it deliberately won't decide for you (EN) →
Every saved scan includes a free Basis Passport export — your evidence-linked basis history as a signed, portable file you can take anywhere. Already holding an IRS letter? Decode it free before you do anything else.
Scanning …
Detecting the format, rebuilding lots, and checking every disposal line.
Nothing leaves this scan — no account, no card, read-only data only.
Your scan is done.
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How this is computed, and why nothing is ever filled in for you (EN) →
| Signal | Value | Status |
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Each of these becomes a plain-language decision card in the full preview after you save — nothing is dropped silently.
Estimates use FIFO defaults on scanned data. The paid rebuild verifies every line to the cent, with evidence.
Save your scan — free full preview
This scan expires on —. Save it to keep going free: connect the rest, resolve decisions, see your complete corrected numbers and what optimization saves you. Your founding price locks at — — pay only when you want the documents.
Saving creates your free account — email only, never a password — and opens your dashboard.
US filer? Check whether the IRS expects an estimated-tax payment by 15 September — the safe harbour is the lesser of two tests, and most people who fear it are already covered.
Unsaved scans auto-delete in 7 days — we mean the privacy promise.
Share the damage (anonymized)
We can read this file — we just need to know which column is which.
Nothing about your export is wrong. It is simply not one of the layouts we recognise on sight, and rather than send you away for want of an adapter, we would rather ask. It takes about thirty seconds and we remember the answer.
The first few rows, exactly as they arrived — scroll sideways to see them all. They are deliberately not reshaped for a small screen: the order your columns come in is the thing you are checking.
03/04/2024 is the 4th of March in one convention and the 3rd of April in the other, and nothing in this file settles which one it uses — no value has a day above the twelfth. We will not pick for you: the choice moves disposals between tax years and decides whether a holding crossed the one-year line.
This is the part we will not guess. Whether a word in your export means a sale or a transfer to your own wallet decides whether tax is owed, and nothing about the row looks wrong either way. Anything left unanswered is listed as skipped — never assumed.
We keep the layout so the next person with this export gets a filled-in form. Your figures are not kept with it, and the mapping is always shown for confirmation rather than applied behind anyone's back.
We couldn’t read that file at all.
A format we don’t recognise is no longer a problem — we would ask you which column is which. This is the other case: the file does not look like a CSV with a header row at all, so there is nothing to ask about. Export it again as CSV and we will take it from there.
The uploaded data still auto-deletes in 7 days. Nothing is kept beyond that.