ALPHA TIER
HISTORICAL
Historical Volatility API /v1/volatility
Comprehensive volatility snapshot at any minute since 2018: realized-vol ladder (5/10/20/30/60d), IV-RV spreads, per-expiry skew, term structure, IV dispersion, GEX/theta by DTE bucket, put/call profile, OI concentration, multi-move hedging, liquidity. Same shape as live /v1/volatility. Realized vols come from QuestDB stocks via SAMPLE BY 1d last-tick.
Coverage
2017-01-03 → 2026-07-17
Granularity
1 minute
Tier
Alpha+
Format
JSON (REST)
Endpoint
Host:
historical.flashalpha.comAuth: X-Api-KeyTier: Alphacurl -H "X-Api-Key: YOUR_API_KEY" \
"https://historical.flashalpha.com/v1/volatility/SPY?at=2026-03-05T15:30:00"
What This Unlocks
- Backtest IV-RV mean reversion - measure IV richness vs RV historically with point-in-time IV / spot.
- Per-expiry skew studies - were skew steepenings before known events real, or noise?
- Term-structure regime classification - contango vs backwardation labels at minute granularity.
- Vol surface mining - per-DTE GEX/theta to find optimal harvest tenors historically.
Related Historical Endpoints
- Historical IV Surface
- Historical VRP
- Historical Options Chain
- Volatility (live) - the live version of this endpoint
Related reading
- Point-in-time greeks for backtesting - why IV and greeks must be reconstructed as-of, not refit with hindsight.
- Complete guide to quant options backtesting - fitting IV-RV studies into a leak-free backtest.