MLB & Baseball Prediction Market Data
Tick-by-tick trades and L2 order-book depth for 107 MLB & Baseball series on Kalshi & Polymarket — MLB game winners, spreads and totals, hits/home-run/strikeout props, first-5-innings lines, KBO and NPB. 15,394 series-days covering May 2025 – present; 17.1M trades · $1.2B turnover over the last 30 captured days. Every contract captured co-located with nanosecond venue and receive timestamps — sold as day bundles, €1 per day, bought as a guest with instant download.
MLB & Baseball on Kalshi & Polymarket
MLB game winners, run lines, totals, first-5-innings lines, player props, season leaders — plus KBO, NPB, LMB and college baseball.
Every series below is archived at full feed resolution — each contract file carries every trade print (price, size, side) and Level-2 order-book updates in one normalized, zstd-compressed schema. A series-day bundle holds all contracts of the series for one UTC day.
Most traded MLB & Baseball series (last 30 days)
Ranked by USD turnover from our own daily statistics — the series a market maker or bot builder should start with.
| # | Series | Venue | Trades (30d) | Turnover (30d) | Days | |
|---|---|---|---|---|---|---|
| 1 | Professional Baseball Game | Kalshi | 7,431,044 | $574.2M | 30 | Buy days |
| 2 | Pro Baseball Total Points | Kalshi | 2,385,981 | $185.3M | 30 | Buy days |
| 3 | MLB (games & props) | Polymarket | 627,430 | $130.5M | 30 | Buy days |
| 4 | Pro Baseball Spread | Kalshi | 1,332,611 | $90.3M | 30 | Buy days |
| 5 | Pro Baseball Run in First Inning | Kalshi | 559,740 | $39.5M | 30 | Buy days |
| 6 | First 5 Innings Total | Kalshi | 424,645 | $21.5M | 30 | Buy days |
| 7 | First 5 Innings Winner | Kalshi | 372,064 | $17.0M | 30 | Buy days |
| 8 | Pro Baseball Team Total | Kalshi | 414,215 | $16.4M | 30 | Buy days |
| 9 | Pro Baseball Strikeouts | Kalshi | 353,893 | $15.6M | 30 | Buy days |
| 10 | Pro Baseball Home Runs | Kalshi | 802,049 | $14.6M | 30 | Buy days |
Trades and USD turnover summed over every contract of the series, from the recorded tick data; 30 days to 2026-09-22. Series without statistics in the window are omitted.
MLB & Baseball activity per venue
| Venue | Series | With stats | Trades (30d) | Turnover (30d) |
|---|---|---|---|---|
| Kalshi | 103 | 84 | 16,436,616 | $1.0B |
| Polymarket | 4 | 4 | 649,304 | $131.7M |
30 days to 2026-09-22, from our own daily statistics per contract.
MLB & Baseball — development since capture
48,679,050 trades and $3.6B of USD turnover across 90 series since 2026-07-08; busiest single series-day 2026-07-29 with $59.3M, biggest contract KXMLBGAME-26SEP152140MIAAZ-MIA (2026-09-16, $4.3M).
| Month | Series active | Days | Trades | Turnover (USD) | Avg / day | Contracts traded | L2 updates | vs previous month |
|---|---|---|---|---|---|---|---|---|
| Sep 2026 (month to date) | 88 | 22 | 12,723,039 | $837.0M | $38.0M | 181,105 | 3.6B | — |
| Aug 2026 | 89 | 31 | 20,771,336 | $1.6B | $50.6M | 157,099 | 3.3B | — |
| Jul 2026 | 45 | 24 | 15,184,675 | $1.2B | $48.3M | — | — | — |
MLB & Baseball series — trades and USD turnover summed per calendar month (UTC) over every contract, from our own daily statistics of the recorded tick data. Days = captured UTC days; a partial month shows no month-over-month change. Contracts traded and L2 (order-book) updates exist for days captured with the extended statistics.
MLB & Baseball — turnover by weekday
Wednesdays are the busiest day at about $61.4M of USD turnover, averaged over the captured days of the last 30.
| Weekday (UTC) | Avg turnover / day | USD | Avg trades | Days |
|---|---|---|---|---|
| Monday | $20.7M | 308.0K | 5 | |
| Tuesday | $38.4M | 558.1K | 5 | |
| Wednesday | $61.4M | 865.5K | 4 | |
| Thursday | $41.3M | 565.9K | 4 | |
| Friday | $27.9M | 402.3K | 4 | |
| Saturday | $42.8M | 682.7K | 4 | |
| Sunday | $43.2M | 672.6K | 4 |
MLB & Baseball series — average USD turnover and trades per weekday over the captured days of the last 30, from our own daily statistics; weekdays without a captured day show —.
Rising MLB & Baseball series — 30 days vs the 30 before
| # | Series | Venue | Turnover (30d) | Prior 30d | Growth (avg / day) | Trades (30d) |
|---|---|---|---|---|---|---|
| 1 | Pro Baseball Gold Glove | Kalshi | $22.9K | $1.7K | +1261.8 % | 876 |
| 2 | Pro Baseball American League Hank Aaron (KXMLBNLHAARON) | Kalshi | $20.2K | $2.2K | +356.4 % | 473 |
| 3 | MLB Wins Leader | Kalshi | $10.4K | $2.6K | +306.9 % | 827 |
| 4 | Pro Baseball American League MVP | Kalshi | $129.4K | $16.4K | +295.6 % | 5,009 |
| 5 | Pro Baseball Award Finalists | Kalshi | $18.1K | $3.4K | +223.1 % | 473 |
Growth of average USD turnover per captured day, the 30 days to 2026-09-22 against the 30 days before; series need ≥ 10 captured days in both windows and ≥ $10K of turnover in the current one. From our own daily statistics.
MLB & Baseball prediction markets — trades and turnover per day
Every captured UTC day of the last 30, summed over the 107 MLB & Baseball series — how much these markets trade day by day, from our own tick capture.
| UTC day | Series with stats | Contracts traded | Trades | Turnover | Buy share | L2 updates |
|---|---|---|---|---|---|---|
| 2026-09-22 | 87 | 6,366 | 434,245 | $31.1M | 64 % | 128.6M |
| 2026-09-21 | 87 | 2,161 | 138,027 | $8.2M | 65 % | 58.2M |
| 2026-09-20 | 87 | 10,210 | 621,937 | $37.4M | 62 % | 256.4M |
| 2026-09-19 | 87 | 10,404 | 723,630 | $40.9M | 64 % | 213.4M |
| 2026-09-18 | 87 | 6,133 | 383,054 | $23.9M | 64 % | 94.7M |
| 2026-09-17 | 87 | 7,418 | 589,524 | $40.1M | 62 % | 132.7M |
| 2026-09-16 | 88 | 10,750 | 1,025,172 | $67.7M | 64 % | 183.9M |
| 2026-09-15 | 88 | 8,523 | 617,439 | $38.8M | 64 % | 164.6M |
| 2026-09-14 | 88 | 4,688 | 226,927 | $13.2M | 68 % | 98.5M |
| 2026-09-13 | 88 | 8,478 | 519,391 | $30.8M | 63 % | 217.9M |
| 2026-09-12 | 88 | 9,336 | 486,646 | $29.3M | 63 % | 167.5M |
| 2026-09-11 | 88 | 6,268 | 260,399 | $16.1M | 66 % | 95.0M |
| 2026-09-10 | 88 | 5,903 | 571,451 | $37.1M | 62 % | 154.3M |
| 2026-09-09 | 88 | 11,700 | 802,132 | $50.3M | 63 % | 264.2M |
| 2026-09-08 | 88 | 7,209 | 497,183 | $31.9M | 65 % | 136.1M |
| 2026-09-07 | 88 | 6,313 | 595,861 | $41.6M | 65 % | 147.4M |
| 2026-09-06 | 88 | 11,556 | 766,862 | $49.9M | 62 % | 221.2M |
| 2026-09-05 | 88 | 11,553 | 663,261 | $43.4M | 64 % | 205.9M |
| 2026-09-04 | 88 | 8,705 | 553,461 | $36.2M | 65 % | 152.4M |
| 2026-09-03 | 88 | 7,977 | 689,153 | $52.0M | 65 % | 132.6M |
| 2026-09-02 | 88 | 11,019 | 899,864 | $68.7M | 65 % | 183.6M |
| 2026-09-01 | 88 | 8,435 | 657,420 | $48.3M | 64 % | 161.0M |
| 2026-08-31 | 88 | 4,551 | 332,787 | $25.1M | 65 % | 86.8M |
| 2026-08-30 | 88 | 7,827 | 782,195 | $54.7M | 64 % | 220.1M |
| 2026-08-29 | 88 | 9,632 | 857,105 | $57.4M | 63 % | 260.8M |
| 2026-08-28 | 88 | 5,982 | 412,321 | $35.6M | 63 % | 111.7M |
| 2026-08-27 | 88 | 4,990 | 413,285 | $36.0M | 58 % | 94.3M |
| 2026-08-26 | 88 | 9,017 | 734,893 | $58.9M | 62 % | 173.6M |
| 2026-08-25 | 88 | 7,273 | 584,136 | $42.0M | 63 % | 130.5M |
| 2026-08-24 | 88 | 3,112 | 246,159 | $15.7M | 65 % | 53.3M |
Per UTC day, summed over every MLB & Baseball series that has statistics for that day, from every trade print of every contract in our tick archive. Trades and USD turnover are exact; contracts traded, buy share and L2 (order-book) updates exist for days captured with the extended statistics — earlier days show —.
Most traded MLB & Baseball contracts on 2026-09-22
The single event contracts with the most USD turnover on the newest captured day — with open and close price and the outcome implied by the last print.
Single contracts ranked by USD turnover on 2026-09-22 (UTC), from every trade print in our tick archive. Prices quote 0..1; the implied outcome reads the last print of the day (≥ 0.97 Yes/Up, ≤ 0.03 No/Down) — venues publish the official result. Each contract’s day file is sold individually, the whole series day as a bundle.
Kalshi MLB & Baseball series
Largest archive first. Each series page lists its exact coverage, day count and recent days; day bundles are bought in the shop calendar.
Polymarket MLB & Baseball series
Largest archive first. Each series page lists its exact coverage, day count and recent days; day bundles are bought in the shop calendar.
| Series | Venue | Interval | Days | Coverage | Size | Price/day | |
|---|---|---|---|---|---|---|---|
| MLB (games & props) | Polymarket | event | 377 | May 2025 – present | 122 GB | €1 | Buy days |
| KBO Baseball (games & props) | Polymarket | event | 209 | October 2025 – present | 6.92 GB | €1 | Buy days |
| NPB Baseball (games & props) | Polymarket | event | 91 | June 2026 – present | 4.20 GB | €1 | Buy days |
| MLB 2026 Regular Season Win Totals | Polymarket | annual | 204 | March 2026 – present | 584 MB | €1 | Buy days |
Why buy MLB & Baseball prediction-market data here
Four things every page on this site is built on — and the reason the numbers above exist at all.
We record everything
The complete public feed of each venue as it was published: every Level-2 snapshot and update at the venue's full book depth, every trade with its aggressor side, every quote, funding, mark-price and liquidation event — for every instrument the venue lists, every UTC day since we added the venue. Nothing sampled, no top-N cut, no on-demand capture.
Institutional grade
Captured co-located at the venue with the exchange timestamp and our receive timestamp in integer nanoseconds, an event-id chain that makes any gap visible, and one normalized schema across 35+ venues — the same capture our own high-frequency trading engine and enterprise feeds run on.
€1 per instrument-day
Any instrument-day is €1, series-day bundles start at €1 — no subscription, no minimum order, no tiers to unlock. Credit packs lower the effective price and never expire, and every venue has free full-day samples to test against first.
Self-service for everyone
Pick the days in the Data Shop, pay by card as a guest and download immediately — no sales call, no enterprise contract, no KYC. Coding agents buy the same files through the MCP server, and the free Agent Skill teaches them the format.
MLB & Baseball prediction-market data — FAQ
Does Kalshi have MLB markets?
Yes — game winners (KXMLBGAME is one of the most-traded Kalshi sports series), spreads, totals, first-3/5/7-innings lines, team totals, player props (hits, home runs, RBIs, total bases, strikeouts, stolen bases), season leaders, awards and World Series markets. Polymarket MLB games and props are one family.
Are Korean and Japanese baseball markets included?
Yes — Kalshi KBO and NPB spreads and totals, the Mexican League (LMB), the World Baseball Classic and college baseball games are listed as their own series.
How far back does the MLB & Baseball data go?
Coverage runs May 2025 – present — 15,394 series-days across 107 series on Kalshi & Polymarket. Each series page lists its exact span.
Can I get MLB & Baseball prediction-market data as CSV or Parquet?
Yes — trades export as gzipped CSV or Parquet at no extra cost, with integer microsecond UTC timestamps that load straight into pandas, polars or DuckDB. Both venues record full order-book depth without a separate BBO stream, so book data ships in the native tick file — the free reader script converts it locally. See the formats overview.
How much does MLB & Baseball prediction-market data cost?
€1 per series-day bundle — every contract of the series for that UTC day — no subscription, no minimum order. Pick days in the shop calendar, pay as a guest, download immediately.
Do I need an account or a sales call?
No. Pick the MLB & Baseball series-days in the Data Shop, pay by card as a guest and download immediately — no subscription, no minimum order, no KYC, no enterprise contract, no sales call. Coding agents buy the same bundles through the MCP server.
How is the MLB & Baseball data captured?
Co-located at the venue, message by message: every Level-2 update and every trade print carries the exchange timestamp and our receive timestamp in integer nanoseconds, an event-id chain makes any gap visible, and one normalized schema across 35+ venues means a parser written for Binance reads these files unchanged. It is the same capture our own high-frequency trading engine runs on — nothing sampled, no top-N cut.
What was the busiest MLB & Baseball trading day?
2026-07-29 — $59.3M of USD turnover over 576,079 trades in a single series-day. Since our statistics began on 2026-07-08, 90 MLB & Baseball series recorded 48,679,050 trades and $3.6B in total; the biggest single contract was KXMLBGAME-26SEP152140MIAAZ-MIA on 2026-09-16 at $4.3M. Wednesdays are the busiest weekday at about $61.4M per day.