Polymarket leads on all 3 live benchmarks. Polymarket wins on Prediction market API rate limits, tested with a daily ramp (200 ms vs 263 ms), Best prediction market API, ranked by live latency and uptime (200 ms vs 277 ms), Polymarket WebSocket latency, live connection and update speed from 3 regions (2.03 s vs 5.0 min).
Read methodology Last measured Window: rolling 24h3 shared benchmarks
CFTC-regulated US prediction market exchange. REST trade API (trade-api/v2) with documented per-tier rate limits; the market data WebSocket requires authentication.
The largest crypto prediction market, settled on Polygon via UMA optimistic oracle. CLOB-style order book hosted on the Polymarket gateway with sub-second publish latency for live odds.
Ramp tiers stay well inside documented budgets where they exist, at most 7 percent of Polymarket's published book allowance, and every run aborts at the first sign of sustained errors. This benchmark measures throttle onset behaviour at polite request rates, not maximum venue throughput.
Uptime here means our probes succeeded from three specific regions at a polite request rate. A venue can be up for us and degraded for you, especially during regional network incidents, and a brief blip between probe cycles can go unrecorded. Treat the panel as a measured signal, not a guarantee.
Connect-to-snapshot includes Cloudflare edge latency and routing from each probe region. Numbers vary with network conditions and market activity. This bench measures observed end-to-end startup time, not venue-side processing time alone.
Frequently asked questions
Kalshi vs Polymarket: which one is better?
Kalshi and Polymarket are compared on 3 shared OpenChainBench benchmarks. Polymarket leads on Prediction market API rate limits, tested with a daily ramp. See the live table on this page for every metric.
Which is faster, Kalshi or Polymarket?
On the Prediction market API rate limits, tested with a daily ramp benchmark, Polymarket leads at 200 ms versus Kalshi at 263 ms. Live measurement is updated continuously by the OpenChainBench harness.
How is the Kalshi vs Polymarket comparison measured?
Every benchmark on this page uses the same open methodology, published at https://openchainbench.com/methodology. Data is CC-BY-4.0. Measurement harnesses are MIT-licensed.
How this pair was selected
Auto-generated pairs require: both providers in the same benchmark for seven consecutive days, at least 1000 samples per provider, observable third-party search demand, and a public /products/[slug] page on OCB. Editorially curated pairs (like this one) may publish early when search demand is high and data is accruing — panels with fewer than 100 samples are shown as provisional. The full pair ledger is versioned in the public repo.
