Delta (Δ)
Your directional exposure — how much you make or lose per ₹1 move in the underlying.
The sensitivity of an option’s price to a ₹1 change in the underlying.
Overview
Delta is the first and most intuitive greek: it tells you how much an option’s price moves when the underlying moves by ₹1, holding everything else constant. It is the slope of the option’s price curve against the spot price.
For a single option, call delta runs from 0 to +1 and put delta from −1 to 0 (often quoted ×100, so 0 to 100). A call that is deep in-the-money behaves almost like the stock itself (delta near 1); a far out-of-the-money option barely reacts (delta near 0); an at-the-money option sits around ±0.5.
Delta doubles as a rough rule of thumb for the probability of finishing in-the-money, and as a hedge ratio — a delta of 0.40 means roughly 40 shares of exposure per option contract of that lot.
A plain-language example
Suppose you buy one NIFTY 24,000 call and the position delta works out to +50 (0.67 × 75-lot).
If NIFTY rises 1 point to 24,001, the position gains roughly ₹50. If NIFTY falls 1 point, it loses roughly ₹50.
A short position (say you sold that call) would have delta −50: you lose ₹50 as the market rises and gain ₹50 as it falls — the exact mirror image.
Calls: 0 to +1 · Puts: −1 to 0 · ATM ≈ ±0.5 · Deep ITM → ±1 · Deep OTM → 0.
Buyers vs sellers
If you buy the option
Long calls are +delta (bullish); long puts are −delta (bearish).
If you sell the option
Short calls are −delta (bearish); short puts are +delta (bullish).
What moves Delta
| When… | Effect on Delta |
|---|---|
| Underlying rises | Call delta increases toward +1; put delta rises toward 0 |
| Moves deeper ITM | Delta magnitude grows toward 1 (option tracks the underlying) |
| Moves deeper OTM | Delta magnitude shrinks toward 0 (option stops reacting) |
| Time to expiry falls | ITM deltas drift to ±1, OTM deltas drift to 0 (delta “polarises”) |
Delta at a glance
How traders use it
- Add up the deltas of every leg to get your net position delta — that single number is your directional bet in underlying-equivalent terms.
- A “delta-neutral” position (net delta ≈ 0) is designed to profit from time or volatility rather than direction.
- Traders use delta as a hedge ratio: to neutralise +150 delta you sell instruments worth −150 delta (futures, or offsetting options).
Watch out for
- Delta is not constant — it changes as the market moves (that rate of change is Gamma). A delta-neutral book does not stay neutral on its own.
- The “delta ≈ probability of expiring ITM” shortcut is an approximation, not an exact figure.
See Delta on a live position
Open the Strategy Builder, add a leg, and hover the Delta row in the Greeks tab to watch it update in real time.
Educational content only — not investment advice. All values are illustrative and do not reflect live quotes. Options carry significant risk; consult a registered adviser before trading.