Upload a CSV, pick a tax year, and preview the gain. Parsing and lot matching run here. The file is not uploaded.
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review with a tax pro
Drop CSV files here, or choose them from disk. They stay in this browser.
No files yet. A fictional sample is the fastest way to see the preview. The two River samples are separate examples of the same account, so load one at a time. Importing both pools the lots.
Specific identification
Used only when the method is specific ID. Keys are outgoing event ids. Quantities are strings.
Add a CSV, then build the preview. The engine loads in this browser when you do. Nothing is uploaded.
Free preview
Choose files and a tax year. Short-term gain, long-term gain, warnings, and the interest summary show up here. The CSV download stays locked.
Ordinary income
Interest, mining, and referral payouts are ordinary income at fair market value. They are not Form 8949 lines. Each one starts a lot.
Form 8949 lots
Each lot defaults to box I when the sale is short-term, or box L when it is long-term. That is the 2025 checkbox for a digital asset with no 1099-DA. Change a lot if a 1099-DA reported basis, or reported the sale and left basis blank. The change is applied in this browser.
| Lot | Sold | Gain | Box | 1099-DA |
|---|
Warnings
Export Form 8949 CSV + Schedule D summary
Launching at $29 per tax year, one-time, not a subscription. This step is locked. The preview above is free. Export unlocks with a license key. This build does not contact a payment service. Enter BASISFIX-DEV to unlock every year, or BASISFIX-DEV-2024 to unlock 2024 only. No payment is processed.
The lot table is omitted from this print. The on-screen preview is free. The full tax packet opens with a license key.