BITCOIN TAX-LOT CLEANUP
A little order.
A lot more clarity.
Bring your Bitcoin records together. Find the missing pieces. Leave with a clearer worksheet for your tax preparer.
On your device. No account, tracking, uploads or saved entries.
Bring your records.
Start with a CSV, enter a transaction, or explore a fictional example. Add more files to combine records from different accounts.
Up to 2 MB per file · 500 total records · Bitcoin and USD only. CSV values stay in memory in this tab. Downloaded files stay on your device until you delete them.
Download the CSV template ↓What should my CSV contain?
Use a UTC timestamp, type (buy, sell or transfer), wallet/account, positive BTC quantity, total USD amount, and BTC fee. For a transfer, include the destination account you own. An optional reference helps trace each record.
Buy: total USD cost including USD purchase fees. Sell: net USD proceeds after eligible USD selling fees. Transfer: one combined row, with no USD amount or fee. Convert your exchange export to this structure; raw deposit/withdrawal rows are not automatically paired.
Fees paid in BTC, swaps, rewards, gifts, mining and other activity are flagged for separate review. Never upload seed phrases, private keys, identity documents or account passwords.
Match your columns
Check every selection. No currency, sign, date format or transaction type is guessed. Blank amounts remain unknown.
Check the details.
Fictional example: record 5 is a duplicate and record 6 is missing its cost. Exclude record 5 and set record 6’s USD cost to 4,000 to see a complete worksheet.
Review your lots.
We check the included records, then match sales and transfers to the earliest acquired lots in that same account. Transfers keep the original acquisition date and basis.
Include complete supported history for each account. This is a U.S. tax-record worksheet, not a tax return or tax owed. A clean check does not establish that your records are complete.
Your records changed. Check them again to update the worksheet.
BEFORE YOU FILE
Good records come first.
What does this tool support?
USD purchases, USD sales and fee-free transfers between accounts you own. Sales and transfers must be dated January 1, 2025 or later; earlier purchases can establish original lots. Include the full supported transaction history for every account, not just the current tax year. The worksheet covers all entered sales, with no tax-year filter.
Other assets, rewards, gifts, inheritance, mining, income, spending, swaps, BTC fees and legacy universal-basis allocations are not calculated. Do not exclude genuine unsupported transactions just to obtain a result: they may change later inventory and basis. Take those records to your preparer.
How should I handle transfers?
Combine the withdrawal and matching deposit into one transfer row only after checking both original records. Enter the originating account and your destination account. This tool models fee-free transfers only. If a transfer includes a BTC or cash fee, preserve the original records for separate review; do not erase or fold the fee into another amount.
Why isn’t there a “lowest tax” method?
Choosing a method after the fact does not establish valid specific identification. This tool illustrates FIFO within each account. Broker requirements, your prior records and any standing instructions may require a different result. It does not reconstruct the transition from universal basis to wallet/account basis in 2025.
Is this ready for Form 8949?
No. The CSV is a review worksheet, not Form 8949. It does not classify holding periods, select reporting boxes, reconcile broker forms, calculate tax or verify whether your history is complete. Review every amount, fee and lot with your preparer. BTC uses integer satoshis; USD is allocated in cents with remainders retained, so splitting lots conserves the entered basis.
What happens to my records?
They are processed locally and kept only in this tab’s memory. There are no analytics, exchange connections, cloud uploads or browser-storage writes. Clear everything or reload to remove entries. Your original files and any downloads remain on your device. Closing the browser does not delete those files.
Educational record organization, not individualized tax advice. Source guidance reviewed October 18, 2026.
IRS: digital asset basis, fees & identification rules ↗IRS: reporting digital assets ↗