resolution parameter controls bucket width for /prices, /metrics, and /books.
Native capture runs at 250 milliseconds for open markets, and every plan can request 250ms — including the free Starter tier. Whole-second 1s buckets remain available. Plans differ on history window, not resolution — see Pricing.
Supported values
Plan restrictions
Resolution is the same on every plan. Only the history window differs: queries with
start_ts older than your lookback return HTTP 403 with the earliest allowed timestamp in the message.
Check live limits on GET /v1/usage:
Selection guide
Finer resolutions return more data points and consume more of your rate limit through pagination.
Timestamp format
The query window is half-open:
[start_ts, end_ts).
Related reading: Historical Polymarket order book data for backtesting explains why capture cadence matters when reconstructing fills.