Everything is built on the Delta Exchange India public API — the venue where these contracts actually trade, in INR margin. Live pages re-read the chain on every request (with short server-side caches, typically 1–5 minutes). Deribit’s DVOL and global open interest appear on the Overview only as market context and are labeled as such.

A recorder snapshots every BTC/ETH/XAUT chain hourly: ATM IV per expiry, straddle marks, expected move, open interest, walls and net gamma. Those snapshots power IV History, OI change and wall history. A separate live recorder keeps a trade tape (every print, April 2024 → today) that powers the Simulator, Flow History and the Radar’s backtests.

Option IVs are the exchange’s mark IV; where a strike quotes both sides, we use the call/put mean. ATM IV per expiry is the mark IV at the strike nearest spot with both sides quoted. Greeks are plain Black-Scholes at mark IV (r = 0), matching the venue’s own convention. The expected move is the ATM straddle mark divided by spot — the market’s own price for movement over that expiry, no model of ours involved.

IV percentile windows: for BTC, short-tenor and ~30d percentiles are computed against 2.2 years of reference data — 810 daily IVs reconstructed from the venue’s own trade tape (Black-76 inversion of near-ATM trades, vega-weighted daily medians; validated against an independent monthly-tenor series) — plus the live hourly record collected since 21 Jul 2026. BTC ~7d, and all ETH/XAUT percentiles, currently rest on the live record alone (~5 weeks and deepening hourly); read those as “vs recent weeks,” not years. Wherever a stat includes the long reference, the page says so.

Three different 0–100 numbers appear near each other. They measure different things:

• Regime conviction (Overview, Brief) — how cleanly current conditions match one playbook (premium selling, premium buying, carry/calendar, directional). It is the dominant bucket’s share of scoring points: low conviction means signals conflict, not that the site is unsure of its data.
• Structure fit (Playbook, Builder fit cards) — how well one specific structure suits the current regime, from a transparent weighted heuristic over IV percentile, VRP, term structure, trend and skew.
• Expiry Radar score — which listed expiry deserves attention today, weighted from IV percentile, term-structure position, tradeability (OI + active strikes; the venue publishes no bid/ask depth) and tenor fit. It is a heuristic, not a validated signal — which is why the Radar also shows measured historical edge separately.

The Radar’s Historical Edge block is measured, not scored: for every historical BTC expiry on the tape, the suggested structure is entered at the last traded prices at/before the entry-DTE checkpoint (no look-ahead; a leg must have actually traded within 48h), held to expiry, settled at intrinsic against the 12:00 UTC settlement, fees included. Win rate, average P&L, profit factor and drawdown are reported per tenor with confidence stars scaled by sample size. When profit factor is below 1 the block now says plainly that the strategy lost money net despite a high win rate.

The Movement engine (Movement Odds) was validated walk-forward over 800 days with 500 out-of-sample days, Brier-scored against a ladder of benchmarks (base rate → raw option-implied → haircut implied → models). The shipped forecast is the only variant that beat raw implied pricing out-of-sample, its full calibration table is published on the page, and every live forecast is logged and scored against what actually happened 24 hours later.

Delta charges options takers min(0.03% of notional, 10% of premium) per option, per side. The payoff builder shows entry fees against the credit; the Radar backtests include fees; the Simulator charges them on every fill. We show entry fees rather than guessing exit fees (which depend on the exit price) — a round trip roughly doubles the entry number. Fees matter more than most parameter choices at this venue’s premium sizes.

• One venue. Everything here covers Delta Exchange; most global BTC option open interest sits elsewhere, so gamma/OI maps understate the whole market.
• Gamma sign is a guess. Dealer-positioning conventions from equity markets may not transfer to crypto — the gamma page carries this warning prominently and shows the mass split by side instead of pretending to know.
• No order-book depth. The public API exposes no bid/ask depth history, so “tradeability” proxies use OI and active strikes.
• Short IV history (see above) behind percentiles, for now.
• Backtests are the past. Fee-in, no-look-ahead replays of what happened — not predictions of what will.

Everything on this site is educational analytics — never investment advice, a signal service, or a prediction. You place, size and own every trade yourself.