Open Interest (Polymarket)

Current open interest for a Polymarket market - the total value of outstanding positions - returned as a point-in-time snapshot.

GET/v2/polymarket/markets/{condition_id}/open_interest

Parameters

condition_idstring (path)required

Polymarket condition ID (path parameter).

condition_idstring

The requested condition ID.

seriesobject[]

OI snapshots over time. Currently a single-point series (latest snapshot only) when data is present, or empty when no OI is captured for this market.

Show 3 fields

tinteger

Snapshot capture timestamp (unix seconds).

total_open_interestnumber

Sum of OI across all outcomes.

by_outcomeobject[]

OI broken down per outcome.

Show 3 fields

outcome_namestring

Internal outcome name.

outcome_labelstring

Display label.

open_interestnumber

OI for this outcome at the snapshot time.

_metaobject

Data warning metadata.

Show 3 fields

data_available_fromnull

null - no historical OI series available.

snapshot_onlyboolean

true - the series contains only the current snapshot, not real history.

warningstring

Plain-text caveat about the data state.