Tick-by-tick Kalshi order book snapshots and deltas, trades, ticker updates and market lifecycle events, as Parquet files.
Frequently asked questions
Yes. New KacData Free Trial accounts include 600 one-time downloads plus 50 downloads per month, for data older than 3 weeks.
Yes. Kalshi order books hold bids only: the yes lists are bids for YES and the nolists are bids for NO. A NO bid at price p is equivalent to a YES ask at 1 − p. KacData keeps Kalshi's yes/no view and does not convert it to bid/ask.
The data is updated once a day（占位，待改）.
Create an account, generate an API key, then download Parquet files directly over HTTP from the KacData API. The dashboard and docs include copy-ready curl and Python examples.
All Kalshi markets from 2026-09-08 (the first day starts at 17:00 UTC) to 2026-11-02（占位，待改）. See Kalshi historical data details.
Yes. KacData is designed for research and backtesting workflows, including tick-level order book replay from the start-of-day book in every L2 file.
Rows are the messages of the Kalshi WebSocket, with local receive timestamps added. Field names are converted to snake_case, prices and sizes are stored as decimals, and each L2 file starts and ends with a synthesized start-of-day and end-of-day order book so a single day can be replayed on its own.
Kalshi data is collected in AWS us-east-2 (availability zone ID use2-az1).