Kalshi Trades API: Whale Trades, Odds & Order Books

Every trade on Kalshi as it prints, with the market's question on the same row: which side was bought, at what price, how many contracts and how many dollars went in. Filter the tape down to the whale trades, one topic (Fed, inflation, weather, elections, sports) or one market.

Also in the same actor: every market with odds, volume and open interest, full order books, and price history in minute, hour or day candles.

Straight from Kalshi's official public trade API. No API key, no Kalshi account, no browser. You pay per row delivered.

Why this one

Most Kalshi actors give you markets and prices. This one gives you the trades: the tape of who-bought-what-size, across the whole exchange or any series, with the dollars already worked out. That is the data you need to spot large bets the moment they happen, or to study how money moved on the Fed decision last month.

Measured on 29 October 2026, one hour of the whole exchange (05:32 to 06:32 UTC):

What	Measured
Trades on all of Kalshi	445,012
Trades of $1,000 or more	1,432 ($4.3M in total)
Of those, paying 95 cents or more per contract	565
Trades of $10,000 or more	56

The biggest trades of that hour that paid 95 cents or less:

Time (UTC)	Paid	Bought	Market
05:41:57	$33,361	YES at $0.33	Will Republicans win the Senate race in Texas? (Ken Paxton)
06:20:55	$22,500	YES at $0.09	Will Republicans win the House in 2026?
06:01:56	$22,100	YES at $0.78	Alibek Kachmazov wins
05:59:19	$19,111	NO at $0.86	Jil Teichmann wins

Try it now

The prefilled input reads the last hour of the whole exchange and returns the 50 newest trades of $1,000 or more that paid 95 cents or less. On Apify it took 11 seconds.

What you get for each trade

Field	What it means
tradedAt	Time of the trade, UTC.
marketTitle, yesOutcome	The market's question, and what a YES contract pays on (for example "Above 5.50%").
side	yes or no: the side the incoming order bought (Kalshi's taker side).
price	Price paid per contract, in dollars from 0 to 1. It is also the market's implied probability for that side.
contracts	Contracts traded. Kalshi allows fractions.
costUsd	Dollars paid: contracts x price. Kalshi's fees are not included.
payoutIfRightUsd, profitIfRightUsd	What those contracts pay if that side wins, and the profit over the cost.
yesPrice, noPrice	Both prices of the trade.
isBlockTrade	Kalshi's block trade flag.
ticker, eventTicker, seriesTicker, seriesTitle, category	Where the market sits: KXFED-26DEC-T4.50, KXFED-26DEC, KXFED, Economics.
marketCloseTime	When the market stops trading.
tradeId, source	Kalshi's trade id, and live or historical.

Four modes

• Trades (default): the tape, filtered by minimum dollars, series, event, market, category or keyword. Newest first.
• Markets: question, last price, mid, bid and ask on both sides, 24 h change, volume, 24 h volume, open interest, close time, rules and result. Most traded first.
• Order books: best YES bid and ask, spread, every price level per side and the contracts resting on each side.
• Price history: candles per minute, hour or day with open, high, low, close and mean price, closing bid and ask, volume and open interest.

How to use it

1. Whale trades right now: Minimum trade size 10000, Lookback 1.
2. Every Fed trade of the last month: Series tickers KXFED, Lookback 720, Minimum trade size 0, Maximum price 100.
3. Big bets on one topic: Keyword bitcoin or Categories Elections, plus a minimum size.
4. The most traded economics markets: What to get Markets, Categories Economics, Minimum 24 h volume 1000.
5. Order books of the busiest Fed markets: What to get Order books, Series tickers KXFED, Markets for order books 5.

Tickers are on every Kalshi market page; the series is the first part (KXFED in KXFED-26DEC-T4.50).

Speed

Measured on 29 October 2026:

Request	Time
Last hour, newest 50 trades of $1,000 or more	11 s
Whole exchange, one full hour, trades of $1,000 or more	154 to 160 s
Fed series, 30 days (247 markets), trades of $100 or more	76 s
All 155,000 open markets, Economics only	32 s

Good to know

• Trades are anonymous. Kalshi does not publish who traded.
• Near-certain bets are left out by default. Many large trades buy an outcome that is already decided (NO at $0.999 on a 15-minute Bitcoin market, for a few dollars of profit). Maximum price 95 skips them; set it to 100 to keep every trade.
• The whole exchange is a lot of tape. Kalshi lets a keyless client read about 3 pages of 1,000 trades per second, so the whole exchange reads at about 2.5 minutes per hour of trades: a one-hour run covers about 20 hours. For days or weeks, give Series, Event or Market tickers: the actor then asks Kalshi market by market, and 30 days of the Fed series took 76 seconds.
• Older trades (before Kalshi's historical cutoff, 29 August 2026 today) are read from Kalshi's historical archive automatically, with source: historical.
• Combo contracts (parlays) are left out unless you turn them on.
• Order books: Kalshi only lists bids. The best YES ask is $1 minus the best NO bid.
• Price history comes only for periods with activity, and only for markets still in Kalshi's live API.

Pricing

Pay per event: one charge per row delivered, whatever the mode (trade, market, order book or price point). Trades and markets filtered out are not charged. Set a maximum total charge on the run if you want a hard cap; when it is reached the run stops and keeps what it already delivered.

Run summary

Each run saves RUN_SUMMARY in the key-value store: trades and pages read, markets looked up, how far back the run got, why it stopped, and the HTTP status of every request.