Who this is for — Futures and options traders: open interest (OI) counts live contracts — unlike volume counting trades. Helps read participation and potential gamma/squeeze.
Open interest (OI) is the total number of derivative contracts (futures, options, perps on some venues) not yet closed or offset — each trade may change OI if opening new exposure or closing existing.
In plain terms — «How many contracts are still open» — higher OI = more capital committed to that instrument/expiry.
OI vs volume
| Metric | Measures |
|---|---|
| Volume | Contracts traded in period |
| Open interest | Stock of open positions |
| OI ↑ + price ↑ | New long money (typical) |
| OI ↓ + price ↑ | Short covering |
On crypto perps some exchanges publish aggregate OI — useful with funding to read leverage.
Operational use
- High OI expiry → roll and volatility risk
- Options: OI by strike = dealer gamma «magnets»
- OI spike + extreme funding → cascade liquidation risk
- Cross-check with COT on CFTC futures
Common mistake — Confusing record volume with new positioning — can be churn without ΔOI.
Example — BTC OI +20% in 48h, price flat, positive funding → crowded long leverage; liquidation flush on breakdown.
Card
- Read with: price, volume, funding.
- Derivatives: Futures, perpetuals.
- Macro positioning: COT report.