DeFi Rate tracks daily Polymarket trading volume, market share, and event data across Polymarket prediction markets. Our charts update weekly and monthly, and can be shared or exported with attribution.
Polymarket Trading Volume & YTD Total
Kalshi monthly trading volume in USD with a running cumulative total for year-to-date.
| Month ISO | Monthly Volume | MoM Change % | Cumulative | YTD YoY % |
|---|---|---|---|---|
| 2025-12 | $2.17B | — | $2.17B | — |
| 2026-01 | $4.19B | ▲ 92.9% | $4.19B | — |
| 2026-02 | $7.26B | ▲ 73.2% | $11.45B | — |
| 2026-03 | $12.22B | ▲ 68.3% | $23.67B | — |
| 2026-04 (partial) | $5.56B | ▼ 11.9% | $29.23B | — |
Polymarket Weekly Volume Chart
Kalshi weekly trading volume in USD. This chart is updated daily with rolling data, with final snapshot on Monday.
Polymarket Volume by Market Category
Kalshi's monthly trading volume split by category. Sports accounts for more than 80% of total volume. The 'Other' category includes Exotics, which are Kalshi's combination markets.
Kalshi vs Polymarket Market Share
Chart provides market share percentage for Kalshi vs. Polymarket on WoW basis. Hover tool tip available.
Methodology
Frequently asked questions
Polymarket uses taker notional volume, which multiplies the number of contracts traded by the price paid at the time of the trade. This differs from Kalshi’s methodology, which multiplies contracts by their $1 face value regardless of price paid.
No. Kalshi counts volume by multiplying contracts by their $1 face value. Polymarket uses taker notional volume, which multiplies contracts traded by the price paid at the time of the trade. The two figures are measuring related but structurally different things, which means direct comparisons require caution.
We try to update all charts update daily. Weekly figures are finalized each Sunday and locked; bars showing the current week reflect volume to date, not a completed week. Monthly figures follow the same daily cycle.
No. The chart uses Polymarket’s international volume. Polymarket US, the CFTC-regulated product, is a separate platform and represents a small fraction of Polymarket’s total activity.
It carries more uncertainty than Kalshi’s. Beyond the methodology issue above, a Columbia University study estimated that roughly 25% of Polymarket’s historical volume reflected wash trading, with the figure running higher in sports markets specifically. Kalshi has a different risk profile on this front.
The change is significant for volume interpretation because the prior zero-fee environment is widely cited as a condition that made wash trading cheap and common on the platform. Whether fees reduce artificial volume meaningfully will become clearer over the coming months.
Not cleanly. The two platforms use different volume methodologies, operate under different regulatory frameworks, and serve partially different user bases. The market share figures on this page use each platform’s reported numbers on a consistent weekly basis, which is the most comparable view available, but the figures should be treated as directional rather than precise.