Crypto capital gains calculator
Drop your exchange or wallet history. Lotsift works out your 2026 short- and long-term crypto gains first-in, first-out per account, with Form 8949 boxes — in your browser, nothing uploaded.
How a crypto gain is worked out
The IRS treats digital assets as property (IRS virtual currency FAQ). Each sale's gain or loss is the proceeds less the cost basis of the coins sold, and it's long-term if you held them more than one year. Since 2025, basis is tracked separately for each wallet or account (Rev. Proc. 2024-28), so a lot bought on Coinbase can't be matched against a sale from your own wallet.
A worked example
The app's sample is a fictional trader with a Coinbase account and a hardware wallet: buys in 2025, a transfer to the wallet, monthly staking rewards and a handful of 2026 sales. Lotsift matches each sale first-in, first-out within its own account. The result: a short-term loss of $2,601.31, a long-term gain of $4,226.33, a net $1,625.02 for Schedule D, and $382.50 of staking income to report as ordinary income. With the sample's prices, the open lots hold $7,803.52 of unrealized losses that could still be realized before December 31.
What you get
- 2026 short-term and long-term totals and the net for Schedule D.
- Form 8949 lines with the box for each — G, H or I in Part I, J, K or L in Part II (Form 8949 instructions).
- Staking and rewards income as ordinary income.
- Open lots with their basis, and the unrealized gain or loss at prices you type.
- Checks: sales with no purchase history, sends to wallets not in the file, Convert rows to split, duplicates, other-year rows.
Files it reads
Coinbase's transaction history CSV works as is. Any CSV or Excel file with a date, a type (Buy, Sell, Send, Receive, Staking or Rewards), an asset, a quantity and a USD value works too — use the template if your exchange's columns are different. Load one file per exchange or wallet; the file name becomes the account.
Your history stays on your computer
Lotsift reads your file with JavaScript in this browser tab. Your transactions are never uploaded, and closing the tab clears them.
How it works
- Drop your transaction history (CSV or Excel), one file per exchange or wallet — or try the sample or the template.
- Read the 2026 totals and every check: missing history, sends to wallets not in the file, Convert rows to split.
- Give the Form 8949 lines to whoever prepares your return, or type prices to see what's worth harvesting before December 31.
FAQ
What does Lotsift do?
It reads your crypto transaction history and works out your 2026 capital gains and losses: each sale matched to the coins you bought, first-in, first-out within each account, split into short-term and long-term, with the Form 8949 box for each line. Staking and rewards income is totalled separately. It doesn't file anything.
Is my data uploaded?
No. Your file is read by JavaScript in your browser tab and never sent to us or anyone else. Transactions aren't stored, so closing the tab clears them. Settings can be saved in this browser.
Which Form 8949 box does each line go in?
Digital assets use boxes G, H and I in Part I (short-term) and J, K and L in Part II (long-term): G or J when a Form 1099-DA reported the basis, H or K when it didn't, I or L when there's no 1099-DA. Lotsift guesses from the account name and the date — brokers report basis for coins bought in the account from 2026 — and the form you receive wins.
When is a gain long-term?
When you held the coins more than one year. A sale on the one-year anniversary is still short-term; the day after is long-term.
How are transfers, fees and rewards handled?
A Send and a Receive between your own accounts moves the lots with their original date and cost. A buy fee adds to basis and a sale fee comes off proceeds. Staking, rewards and airdrops are ordinary income at their USD value when received, and that value becomes their basis.
What about crypto-to-crypto trades?
A trade is a sale of one coin and a purchase of the other. Enter a Sell row and a Buy row with the same date and USD value. Convert or swap rows are flagged, not guessed.
What's free?
Importing any number of rows, the 2026 totals, the totals by box, the harvest view and every check, plus the first 10 Form 8949 lines on screen and in print (with a footer). Pro shows and prints every line and exports the Form 8949 CSV, the Excel workbook and the open lots CSV.
What isn't covered?
It doesn't handle every DeFi case: liquidity pools, lending, staking derivatives, wrapping, bridges and LP tokens need your own treatment. Also not covered: state tax, the collectibles rate for NFTs, margin and futures, mining or business income, gifts and inheritances, specific-identification lot choices and wash-sale adjustments (a loss with a rebuy of the same asset within 30 days is flagged, not changed). It's FIFO only and US dollars only.
Is this tax advice?
No. Lotsift applies the rules it describes to the data you provide. Ask your tax adviser what applies to you.