World Series & MLB Playoffs Prediction Market
Tick-by-tick trades and L2 order-book depth for 10 World Series & MLB Playoffs series on Kalshi — World Series winner (KXMLB), AL and NL Championship, playoff qualifiers, playoff matchups, best record, longest winning streak. 1,863 series-days covering March 2026 – present; 144.8K trades · $2.8M 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.
World Series & MLB Playoffs on Kalshi
World Series winner, AL/NL pennants, playoff qualifiers and matchups, best and worst records, win/loss streaks.
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 World Series & MLB Playoffs 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 | Pro Baseball Playoff Qualifiers | Kalshi | 18,785 | $1.2M | 30 | Buy days |
| 2 | World Series | Kalshi | 85,719 | $1.0M | 30 | Buy days |
| 3 | MLB American League Championship | Kalshi | 13,243 | $213.7K | 30 | Buy days |
| 4 | MLB National League Championship | Kalshi | 11,051 | $165.6K | 30 | Buy days |
| 5 | Pro Baseball Best Record (KXMLBBESTRECORD) | Kalshi | 7,343 | $77.8K | 30 | Buy days |
| 6 | Pro Baseball Best Record (KXMLBWORSTRECORD) | Kalshi | 2,557 | $30.9K | 30 | Buy days |
| 7 | Teams in MLB Finals | Kalshi | 5,613 | $20.4K | 30 | Buy days |
| 8 | Longest Winning Streak | Kalshi | 150 | $5.8K | 30 | Buy days |
| 9 | Longest Losing Streak | Kalshi | 232 | $2.4K | 30 | Buy days |
| 10 | Pro Baseball Playoff Matchups | Kalshi | 98 | $1.9K | 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.
World Series & MLB Playoffs — development since capture
220,522 trades and $3.9M of USD turnover across 10 series since 2026-07-08; busiest single series-day 2026-08-09 with $139.6K, biggest contract KXMLB-26-LAD (2026-08-09, $113.9K).
| Month | Series active | Days | Trades | Turnover (USD) | Avg / day | Contracts traded | L2 updates | vs previous month |
|---|---|---|---|---|---|---|---|---|
| Sep 2026 (month to date) | 10 | 22 | 107,784 | $2.2M | $100.3K | 2,255 | 58.0M | — |
| Aug 2026 | 10 | 31 | 111,124 | $1.7M | $54.8K | 2,615 | 68.7M | — |
| Jul 2026 | 1 | 24 | 1,614 | $9.9K | $412.65 | — | — | — |
World Series & MLB Playoffs 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.
World Series & MLB Playoffs — turnover by weekday
Sundays are the busiest day at about $112.8K of USD turnover, averaged over the captured days of the last 30.
| Weekday (UTC) | Avg turnover / day | USD | Avg trades | Days |
|---|---|---|---|---|
| Monday | $97.6K | 5.1K | 5 | |
| Tuesday | $92.6K | 4.9K | 5 | |
| Wednesday | $99.5K | 5.0K | 4 | |
| Thursday | $80.4K | 4.2K | 4 | |
| Friday | $74.6K | 3.7K | 4 | |
| Saturday | $84.9K | 5.2K | 4 | |
| Sunday | $112.8K | 5.6K | 4 |
World Series & MLB Playoffs 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 World Series & MLB Playoffs series — 30 days vs the 30 before
| # | Series | Venue | Turnover (30d) | Prior 30d | Growth (avg / day) | Trades (30d) |
|---|---|---|---|---|---|---|
| 1 | Pro Baseball Playoff Qualifiers | Kalshi | $1.2M | $312.6K | +95.2 % | 18,785 |
| 2 | Pro Baseball Best Record (KXMLBWORSTRECORD) | Kalshi | $30.9K | $10.3K | +49.2 % | 2,557 |
| 3 | Pro Baseball Best Record (KXMLBBESTRECORD) | Kalshi | $77.8K | $27.3K | +42.6 % | 7,343 |
| 4 | MLB American League Championship | Kalshi | $213.7K | $76.6K | +39.5 % | 13,243 |
| 5 | MLB National League Championship | Kalshi | $165.6K | $60.1K | +37.7 % | 11,051 |
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.
World Series & MLB Playoffs prediction markets — trades and turnover per day
Every captured UTC day of the last 30, summed over the 10 World Series & MLB Playoffs 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 | 10 | 98 | 5,869 | $105.1K | 74 % | 1.2M |
| 2026-09-21 | 10 | 97 | 6,326 | $144.6K | 50 % | 850.6K |
| 2026-09-20 | 10 | 98 | 6,851 | $173.2K | 60 % | 1.1M |
| 2026-09-19 | 10 | 106 | 7,172 | $134.6K | 55 % | 1.2M |
| 2026-09-18 | 10 | 91 | 4,265 | $126.5K | 68 % | 713.9K |
| 2026-09-17 | 10 | 100 | 4,689 | $99.2K | 69 % | 832.7K |
| 2026-09-16 | 10 | 103 | 6,241 | $167.8K | 54 % | 2.2M |
| 2026-09-15 | 10 | 100 | 5,139 | $124.4K | 62 % | 1.9M |
| 2026-09-14 | 10 | 101 | 5,398 | $98.7K | 72 % | 1.8M |
| 2026-09-13 | 10 | 96 | 5,844 | $106.4K | 68 % | 3.6M |
| 2026-09-12 | 10 | 98 | 3,700 | $60.7K | 64 % | 2.2M |
| 2026-09-11 | 10 | 97 | 3,141 | $44.2K | 68 % | 1.8M |
| 2026-09-10 | 10 | 104 | 4,608 | $99.2K | 60 % | 4.2M |
| 2026-09-09 | 10 | 102 | 4,164 | $100.7K | 36 % | 3.4M |
| 2026-09-08 | 10 | 99 | 2,848 | $59.3K | 53 % | 2.6M |
| 2026-09-07 | 10 | 102 | 3,417 | $83.2K | 60 % | 4.8M |
| 2026-09-06 | 10 | 109 | 4,357 | $92.1K | 74 % | 5.4M |
| 2026-09-05 | 10 | 109 | 4,308 | $78.7K | 64 % | 3.3M |
| 2026-09-04 | 10 | 109 | 3,968 | $85.5K | 62 % | 3.3M |
| 2026-09-03 | 10 | 114 | 4,866 | $83.6K | 64 % | 4.0M |
| 2026-09-02 | 10 | 109 | 5,287 | $73.2K | 57 % | 4.8M |
| 2026-09-01 | 10 | 113 | 5,326 | $65.0K | 67 % | 2.8M |
| 2026-08-31 | 10 | 103 | 4,218 | $83.1K | 68 % | 2.8M |
| 2026-08-30 | 10 | 113 | 5,332 | $79.7K | 72 % | 5.0M |
| 2026-08-29 | 10 | 104 | 5,452 | $65.7K | 64 % | 5.4M |
| 2026-08-28 | 10 | 107 | 3,513 | $42.1K | 64 % | 4.8M |
| 2026-08-27 | 10 | 102 | 2,702 | $39.6K | 52 % | 2.5M |
| 2026-08-26 | 10 | 115 | 4,288 | $56.3K | 68 % | 3.8M |
| 2026-08-25 | 10 | 122 | 5,352 | $109.0K | 45 % | 4.4M |
| 2026-08-24 | 10 | 115 | 6,150 | $78.3K | 63 % | 1.8M |
Per UTC day, summed over every World Series & MLB Playoffs 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 World Series & MLB Playoffs 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.
| Contract | Series | Venue | Open → Close | Implied outcome | Trades | Turnover | |
|---|---|---|---|---|---|---|---|
| KXMLB-26-MIL | World Series | Kalshi | 0.163 → 0.173 | open | 741 | $13.2K | buy file → |
| KXMLBPLAYOFFS-26-SD | Pro Baseball Playoff Qualifiers | Kalshi | 0.980 → 0.980 | Yes | 22 | $10.5K | buy file → |
| KXMLB-26-LAD | World Series | Kalshi | 0.311 → 0.303 | open | 504 | $9.9K | buy file → |
| KXMLBAL-26-TB | MLB American League Championship | Kalshi | 0.290 → 0.320 | open | 353 | $8.5K | buy file → |
| KXMLBPLAYOFFS-26-CWS | Pro Baseball Playoff Qualifiers | Kalshi | 0.960 → 0.970 | Yes | 43 | $7.8K | buy file → |
| KXMLBPLAYOFFS-26-CLE | Pro Baseball Playoff Qualifiers | Kalshi | 0.970 → 0.990 | Yes | 44 | $4.6K | buy file → |
| KXMLBNL-26-MIL | MLB National League Championship | Kalshi | 0.270 → 0.280 | open | 77 | $4.0K | buy file → |
| KXMLBPLAYOFFS-26-HOU | Pro Baseball Playoff Qualifiers | Kalshi | 0.450 → 0.410 | open | 66 | $3.5K | buy file → |
| KXMLBBESTRECORD-26-MIL | Pro Baseball Best Record (KXMLBBESTRECORD) | Kalshi | 0.790 → 0.680 | open | 239 | $3.5K | buy file → |
| KXMLBNL-26-LAD | MLB National League Championship | Kalshi | 0.410 → 0.410 | open | 114 | $3.4K | buy file → |
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 World Series & MLB Playoffs 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 | |
|---|---|---|---|---|---|---|---|
| World Series | Kalshi | event | 203 | March 2026 – present | 3.33 GB | €1 | Buy days |
| Pro Baseball Playoff Qualifiers | Kalshi | annual | 203 | March 2026 – present | 1.38 GB | €1 | Buy days |
| Teams in MLB Finals | Kalshi | event | 203 | March 2026 – present | 1.28 GB | €1 | Buy days |
| MLB American League Championship | Kalshi | annual | 203 | March 2026 – present | 926 MB | €1 | Buy days |
| MLB National League Championship | Kalshi | annual | 203 | March 2026 – present | 657 MB | €1 | Buy days |
| Pro Baseball Playoff Matchups | Kalshi | event | 36 | August 2026 – present | 450 MB | €1 | Buy days |
| Pro Baseball Best Record (KXMLBBESTRECORD) | Kalshi | annual | 203 | March 2026 – present | 325 MB | €1 | Buy days |
| Pro Baseball Best Record (KXMLBWORSTRECORD) | Kalshi | annual | 203 | March 2026 – present | 302 MB | €1 | Buy days |
| Longest Winning Streak | Kalshi | event | 203 | March 2026 – present | 243 MB | €1 | Buy days |
| Longest Losing Streak | Kalshi | event | 203 | March 2026 – present | 105 MB | €1 | Buy days |
Why buy World Series & MLB Playoffs 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.
World Series & MLB Playoffs prediction-market data — FAQ
Does Kalshi have a World Series market?
Yes — KXMLB is the season-long World Series winner series; AL/NL Championship, playoff qualifiers, playoff matchups, best/worst record and streak series sit beside it. Each day of the season is one bundle day.
How is World Series prediction-market data sold?
One purchase covers every contract of the series for one UTC day — every trade print and the complete Level-2 book per contract, captured co-located with nanosecond timestamps — €1 per series-day, bought as a guest with instant download.
How far back does the World Series & MLB Playoffs data go?
Coverage runs March 2026 – present — 1,863 series-days across 10 series on Kalshi. Each series page lists its exact span.
Can I get World Series & MLB Playoffs 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. Kalshi records 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 World Series & MLB Playoffs 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 World Series & MLB Playoffs 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 World Series & MLB Playoffs 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 World Series & MLB Playoffs trading day?
2026-08-09 — $139.6K of USD turnover over 5,910 trades in a single series-day. Since our statistics began on 2026-07-08, 10 World Series & MLB Playoffs series recorded 220,522 trades and $3.9M in total; the biggest single contract was KXMLB-26-LAD on 2026-08-09 at $113.9K. Sundays are the busiest weekday at about $112.8K per day.