FillBook — The trade journal for Kalshi traders
The Kalshi trade journal<br>See what your Kalshi trading actually makes you, after fees<br>Connect read-only and get your real P&L with fees folded in, win rate by category, and where your edge actually is. The math a spreadsheet or a generic journal can't do.<br>Start freeSee a live demo, no signup<br>Free forever plan · No card required · Read-only imports<br>fillbook.io/demo
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Generic trading journals weren't built for this<br>Stock and options journals can't import a Kalshi API key, don't understand contracts that settle to $1 or $0, and have no idea what "politics," "econ" or "weather" edge means. So Kalshi traders end up in spreadsheets — or flying blind.
Everything a prediction-market trader needs to review their book<br>Auto-import from Kalshi<br>Paste a read-only Kalshi API key. We pull your fills and settlements, normalize them, and group them into positions. CSV upload too.
P&L you can trust<br>Realized P&L with fees folded in, weighted-average cost on partial closes, and correct settlement to $1/$0. The number is the whole point — we get it right.
Edge by category<br>Win rate and average win/loss broken down by market category — politics, sports, weather, econ, crypto — and by venue and day of week. Find where your edge actually is.
A real journal<br>Notes and tags on every position: your thesis, your setup, your mistakes, your emotions. Review your losses and stop repeating them.
Edge decay<br>See P&L by holding duration — an early read on whether your edge fades the longer you sit in a position.
Your data, yours<br>We never place trades. We never sell your data. Delete everything on request. Read-only, from day one.
Simple pricing<br>Start free. Upgrade when your book outgrows one venue.<br>Free
$0 forever<br>✓Unlimited trade storage<br>✓60-day analytics window<br>✓Journal notes + tags<br>Start free<br>Pro
$15 /month<br>✓Everything in Free<br>✓Full-history analytics (all-time)<br>✓Every future Pro feature<br>Go Pro
Frequently asked<br>Is my Kalshi API key safe?<br>We ask for a read-scoped key and encrypt the private key at rest. We only read fills, positions and settlements — we can't place or cancel orders.
How is P&L calculated?<br>Per position (one market, one side), using weighted-average cost for partial closes, with trading fees subtracted and settlement to $1 or $0 per contract. For Kalshi we use the exchange's reported per-fill fee, so the number matches your account.
Which venues do you support?<br>Kalshi today. Polymarket and other venues are on the roadmap — driven by demand, so tell us what you trade.
Can I cancel anytime?<br>Yes. Pro is month-to-month; cancel whenever and you keep access through the period you paid for.
Stop guessing where your edge is<br>Import your fills in minutes. See the truth about your trading.<br>Start free
© 2026 FillBook. Not affiliated with Kalshi. We never place trades.