Wetin be Option Gamma? Delta Accelerator

Gamma na di option greek wey dey measure how fast delta dey change. If delta na di option speed against di stock, gamma na im acceleration — how much delta move for every $1 move for di underlying. Na im be di reason why one calm option fit turn explosive: as di stock dey move, gamma na wetin dey reshape di whole position. Two forces dey drive am, and both dey show for real data.

Gamma dey climb as expiry dey near

Dis na di gamma for our SPY $740 call over im final seven weeks:

SELECT date,
       round(avg(gamma), 4) AS gamma
FROM global_markets.options_greeks
WHERE ticker = 'O:SPY260618C00740000' AND date BETWEEN '2026-05-01' AND '2026-06-17' AND implied_volatility > 0.02
GROUP BY date ORDER BY date

Gamma no just rise — e track di strike. E start near 0.0105 and run highest for di days wey SPY sit right around $740, e dey spike anytime di stock dey hover on di strike with only weeks to run. Two forces dey set gamma, and di SPY board separate dem. First, TIME: di delta of one at-the-money option dey react more to each move di nearer e get to expiry, so gamma dey climb steeply as di clock dey run down:

SELECT multiIf(days_to_expiry<=7,'0-7 days',days_to_expiry<=30,'8-30 days',
               days_to_expiry<=90,'31-90 days','90+ days') AS time_to_expiry,
       round(avg(gamma), 4) AS avg_gamma
FROM global_markets.options_greeks
WHERE date = '2026-07-13' AND underlying_symbol = 'SPY' AND abs(delta) BETWEEN 0.45 AND 0.55
GROUP BY time_to_expiry ORDER BY min(days_to_expiry)

One same-day option carry many times di gamma of one three-month option for di same strike. Dis na di coiled spring behind one 0DTE trade: near expiration, di delta of one at-the-money contract fit swing from 0.2 to 0.8 on one small move, and im value dey lurch with am. E still be di mechanism wey dem name for "gamma squeeze" — dealers wey short plenty short-dated calls must buy stock as e dey rise to stay hedged, and dat buying dey push di stock higher still, one squeeze wey come from option positioning instead of fundamentals.

Gamma dey largest at the money

Di second force na moneyness. Fix di expiry and vary di strike, and gamma na one bell wey center on di current price:

SELECT multiIf((strike_price/underlying_close-1)<-0.04,'deep ITM',
               (strike_price/underlying_close-1)<-0.015,'ITM',
               (strike_price/underlying_close-1)<0.015,'ATM',
               (strike_price/underlying_close-1)<0.04,'OTM','deep OTM') AS moneyness,
       round(avg(gamma), 4) AS avg_gamma
FROM global_markets.options_greeks
WHERE date = '2026-07-13' AND underlying_symbol = 'SPY' AND option_type = 'C'
  AND days_to_expiry BETWEEN 25 AND 40
GROUP BY moneyness ORDER BY avg(strike_price/underlying_close)

One deep-in-the-money call already dey move nearly one-for-one with di stock, so small room dey for delta to change; one deep-out-of-the-money call barely react. Na only di at-the-money strike dey sit on di knife edge, where one small move dey flip di odds — and na there gamma dey concentrate. Combine di two forces and di maximum-gamma option na di one wey dey at the money AND near expiry, exactly di profile wey dey make short-dated at-the-money options feel electric.

Gamma and di hedge wey never dey sit still

For anybody wey dey hold options, gamma na di reason why one hedge dey drift. One desk wey sell calls and buy stock to be delta-neutral go find say im delta dey move di instant di stock move — negative gamma mean say di hedge always dey one step behind, e dey force am to buy high and sell low to re-hedge. Dat constant adjustment, across di market largest positions, na one real force on di tape near big expirations, part of how market makers dey make money.

For one retail trader di read dey simpler: gamma dey tell you how stable your delta be. One low-gamma position — deep in the money, or months out — dey behave predictably. One high-gamma position — at the money, days to expiry — dey twitchy. And gamma never dey come free: di contracts with di most of am still carry di fastest time decay, so one buyer wey dey pay for explosive potential dey pay for am every day di move no come.

FAQ

Wetin be gamma for options in simple terms?

Gamma na how fast one option delta dey change when di stock move $1. If delta na di option speed, gamma na im acceleration. High gamma mean say delta — and di option value — fit change quickly on one small move.

Why gamma dey highest at the money?

One at-the-money option na di most uncertain about finishing in or out of the money, so one small stock move dey change im odds di most — and delta with am. Deep in- or out-of-the-money options already near-certain either way, so dia delta barely dey move and gamma dey small.

Why gamma dey increase near expiration?

With small time remain, di fate of one at-the-money option dey turn on di next small move, so im delta dey react violently — high gamma. Longer-dated options get time to absorb moves, so dia delta dey shift gently and gamma dey stay low.

High gamma good or bad?

E depend on your side. One buyer like positive gamma — di position dey accelerate for dia favor on one big move. One seller dey short gamma and big moves for either direction dey hurt am, di risk wey dem collect premium for.

Wetin be gamma squeeze?

Na one feedback loop: dealers wey short plenty short-dated call options must buy di underlying stock as e dey rise to stay hedged (negative gamma dey force am). Dat buying fit push di stock higher, e dey force still more hedging — one squeeze wey come from option positioning instead of fundamentals.