The Free GEX Calculator computes gamma exposure for any US-listed ticker with liquid options. Enter a ticker and pick an expiration; the tool returns the net gamma exposure, the Call Wall strike, the Put Wall strike, and the Gamma Flip level — all in a few seconds.
Free to use. No account required.
What this tool does
Gamma Exposure (GEX) measures how option dealer hedging affects price action on the underlying stock or index. The calculator aggregates open interest across strikes and expirations, applies the standard GEX formula, and returns the key levels that directional traders watch:
- Net GEX — total gamma exposure across all open contracts
- Call Wall — the strike with the largest positive call gamma (often acts as resistance)
- Put Wall — the strike with the largest positive put gamma (often acts as support)
- Gamma Flip — the price level where dealer regime transitions from stabilizing to destabilizing hedging
Who it's for
Directional traders and options enthusiasts who want to read market structure without paying for a dedicated platform. Day traders, swing traders, and anyone trading SPY, SPX, QQQ, or heavily-optioned single names will find GEX useful for spotting structural levels that price action respects.
How to use it
- Enter a ticker in the input field. Works best on high-liquidity names with rich options markets.
- Pick one or more expirations from the list. Near-term expirations matter most for intraday context; monthly expirations carry more structural weight.
- Click Calculate. Results appear in a few seconds.
- Read the key levels — Net GEX, Call Wall, Put Wall, Gamma Flip.
- Compare to current price to understand where you are in the structure.
What the output tells you
A positive net GEX means dealers are net long gamma. Their hedging dampens moves — expect range-bound or mean-reverting price action.
A negative net GEX means dealers are net short gamma. Their hedging amplifies moves — expect trending action with larger-than-usual swings.
Price approaching the Call Wall often stalls or reverses; breakouts above tend to accelerate as dealer hedging flips direction.
Price approaching the Put Wall often finds support; breakdowns below tend to cascade as hedging adds to the move.
Price crossing the Gamma Flip marks a regime change — the character of trading often shifts within minutes.
Image below from a paid version of GEX:
Limitations of the free version
The Free GEX Calculator gives you a snapshot. For active trading you typically want:
- Real-time auto-refresh as dealer positioning changes throughout the session
- Historical replay to study how GEX evolved during past sessions
- AI-generated commentary that interprets the current setup
- Multi-ticker workspaces to monitor SPY, QQQ, and individual names simultaneously
- Vanna and Charm — second-order Greeks that matter during IV events and expiration week
These are available in QuantWheel's authenticated GEX suite, which includes GEX AI, the full Heatmap, Replay, and the Gamma Flip alerts system.
Related tools
- Free GEX Heatmap — see gamma exposure across strikes and expirations as a 2D heatmap
- Free Max Pain Calculator — find the strike where the most open contracts expire worthless
- Understanding GEX and what it tells you — deeper explanation of the mechanics