Gamma exposure, or GEX, estimates how much stock options dealers have to buy or sell to stay hedged as price moves. Mapped by strike, it shows where that hedging is likely to dampen moves and where it is likely to accelerate them. A few years ago it was a professional-desk number. Today a dozen retail tools publish it, at prices from free to several hundred dollars a month.
The tools look similar on a product page and differ a lot underneath: how often the numbers update, how many symbols they cover, which levels they mark, and what they assume about who holds each option. This guide puts nine GEX tools side by side on those points, using only what each vendor states on its own pricing, feature and help pages, and then covers the free GEX charts worth knowing.
Robinflow is one of the nine. We have tried to be fair, and we say plainly where a competitor is stronger. If GEX itself is new to you, start with how to read gamma exposure.
Key Takeaways
- Entry prices for a plan that includes GEX range from $19 to $150 a month across the nine tools compared here, based on each vendor's own pages (figures as of Oct 29, 2026).
- Update speed ranges from every second (GEXBot) and every 2 minutes (Volland) to every 5 minutes (Tradytics), hourly (Robinflow, for the most active symbols) and 15 minutes delayed (OptionCharts Premium).
- Symbol coverage ranges from 56+ symbols (GEXBot) to about 4,500 (Volland) and every U.S. symbol with listed options (Robinflow, Unusual Whales).
- Every GEX number is an estimate. Public open interest does not say who holds each contract, so each tool applies its own assumption, and the ones that disclose it disclose different things.
- Free GEX exists: SqueezeMetrics publishes an S&P 500 GEX history chart, SpotGamma a daily SPX gamma chart, OptionCharts a single-expiration chart, and Robinflow full symbol pages 3 sessions delayed.
At a Glance
| Tool | Cheapest plan with GEX | Free trial or tier | Update speed (vendor's words) | Symbols covered | Options flow in same plan |
|---|---|---|---|---|---|
| Robinflow | $19/mo through Nov 30, then $39/mo | 7-day free trial, full access | Hourly in session for the most active symbols; all symbols before the open and after the close | Every optionable U.S. symbol | Yes |
| OptionCharts | $20/mo, billed annually | Free chart, one expiration | 15 min delayed; real-time on $35 plan | Not stated | Not stated |
| Unusual Whales | $50/mo | Free account, GEX not stated | "Real-Time" | "All US Tickers" | Yes |
| GEXBot | $50/mo | No free trial stated | "every second" | 56+ | Classified orderflow on higher tiers |
| Tradytics | $69/mo | Paid, $15 for 15 days | Ticker dashboard every 5 min | Not stated | Yes |
| SpotGamma | $99/mo | Free SPX chart and newsletter | Real-time for S&P 500 (TRACE) | 3,500+ (Equity Hub) | Yes |
| Cheddar Flow | $99/mo | Trial excludes the GEX plan | "Real time" | Not stated | Yes |
| MenthorQ | $129/mo ($59 first month) | Free account, delayed data | Not stated | 1,000+, including futures | No |
| Volland | $150/mo | Not stated | "every 2 minutes" | About 4,500 | No |
"Not stated" means the vendor's public pages did not say as of our latest check on Oct 29, 2026. The full comparison further down adds key levels, methodology and history, with each vendor's own wording.
What to Look For
Update Speed
GEX is built from open interest, which the exchanges publish once a day before the open, plus the current price and implied volatility, which change all day. A tool that recomputes once per session tells you the structure going into the day. A tool that recomputes every few minutes, or blends in the day's volume, tells you how that structure is shifting. Swing traders mostly need the first. 0DTE and intraday SPX traders need the second, and should check whether the fast updates cover the symbol they trade or only the S&P 500.
Symbol Coverage
Many GEX tools started with SPX and still focus there. If you trade single stocks, check coverage before anything else. The range in this comparison runs from 56+ symbols to every optionable U.S. symbol, and some vendors cover thousands of stocks with daily levels but give only the index products their intraday views.
Key Levels
The headline outputs are the call wall and put wall, the strikes with the heaviest positive gamma above and below price, and the zero-gamma or flip level where the chain turns from negative to positive gamma. Some vendors add proprietary levels with their own names. Proprietary is fine, but you should know whether a level is a straightforward calculation or a model you cannot check.
Strike by Expiration
A single GEX-by-strike bar chart adds every expiration together. That hides the fact that a large 0DTE wall disappears at 4 pm while a monthly wall sticks around for weeks. Tools that break exposure out by expiration, or show a strike-by-expiration heatmap, let you see which walls will still be there tomorrow.
The Assumption Behind the Number
This is the part most product pages skip. Open interest tells you how many contracts exist at a strike, not who owns them. The classic convention assumes dealers are long the calls and short the puts customers trade. Other tools assume market makers are on every trade, or classify each trade by where it printed against a theoretical value. These choices can flip the sign of a strike. A tool that tells you its assumption is easier to trust than one that does not.
Nine GEX Tools Compared
Every fact below comes from the vendor's own pricing, feature or help pages. We keep this comparison current by rechecking each vendor's pages as they change; figures are as of Oct 29, 2026. Where a vendor did not state something, the cell says "not stated" rather than guessing. Prices are list prices for monthly billing unless noted.
| Tool | Price with GEX | Update speed | Coverage | Key levels and views | Dealer assumption (vendor's words) | History |
|---|---|---|---|---|---|---|
| Robinflow | $19/mo, $190/yr through Nov 30; $39/mo, $399/yr from Dec 1 | Hourly from 10 AM to 3:45 PM ET for the ~200 most active symbols; every symbol before the open and after the close | Every optionable U.S. symbol | Strike × expiration heatmap, call and put walls, estimated flip, net GEX | Open interest with "standard dealer-positioning assumptions," stated as an estimate | Daily history with a date picker |
| OptionCharts | $20/mo billed annually ($240/yr); real-time $35/mo ($420/yr) | "15 minutes delayed" on Premium; real-time on Ultimate | Not stated | GEX by strike and by expiration, call wall, put wall, gamma flip, DEX | Dollar value "option sellers must hedge for every 1% change" | GEX history chart; depth not stated |
| Unusual Whales | $50/mo Basic, $504/yr | "GEX Heatmap in Real-Time"; SPX exposure "10-min CBOE updates" ($120 plan: 1 min) | "All US Tickers" | Exposure by strike and expiration, DEX, vanna; call wall, put wall and flip in its API | "GEX assumes that market makers are part of every transaction" | Not stated for the dashboard |
| GEXBot | $50/mo Classic | "Real-time GEX calculation every second" | 56+ symbols, mainly indexes and liquid names | Zero gamma, major positive and negative levels, net GEX; vanna and charm from $150 | Classic: "naive GEX with standard netting"; higher tiers classify trades against theoretical value | 90-day archive |
| Tradytics | $69/mo Pro | Options ticker dashboard "every 5 minutes" | Not stated | Delta, gamma and vanna exposure, charm flows | Not stated | Not stated |
| SpotGamma | $99/mo Essential | HIRO and TRACE real-time; TRACE is S&P 500 only | 3,500+ stocks in Equity Hub; key levels for major indices | Call wall, put wall, zero gamma, proprietary Volatility Trigger; S&P 500 heatmap | Liquidity providers "are short put options and long calls," plus a proprietary inventory model | 10-day key level history in Equity Hub |
| Cheddar Flow | $99/mo Pro, $900/yr | "Real time gamma exposure data" | Not stated | Exposure across strikes and expirations, call and put walls, 1-day expected move | Not stated; metrics use "a 1% underlying move" | Not stated |
| MenthorQ | $129/mo Premium ($59 first month) | Not stated | 1,000+ symbols including futures | Call resistance, put support, high volatility level, net GEX by strike, 0DTE levels | Not stated | Not stated |
| Volland | $150/mo Swing | "updates every 2 minutes"; 0DTE widget every 5 min ($250) | About 4,500 symbols | Exposure charts; vanna, charm and more on higher tiers | Proprietary, from "the real-time quote feed" | Not stated |
A few things stand out.
Price does not track speed. GEXBot recomputes every second for $50 a month, while some tools charge two to three times that without stating an update frequency at all. What you pay for further up the range is usually breadth: more greeks, more symbols, newsletters, education and community.
Fast and broad rarely come together. The fastest tools cover the fewest symbols (GEXBot) or restrict their fastest view to the S&P 500 (SpotGamma's TRACE, Unusual Whales' SPX exposure). The broadest tools update less often. Decide which matters more for how you trade.
Methodology disclosure is uneven. SpotGamma, Unusual Whales, GEXBot and OptionCharts all say something specific about how they treat dealer positioning, and their answers differ. Four of the nine say nothing we could find. Two tools showing different walls for the same symbol are often both right under their own assumptions.
Key level names are not standard. Call wall, put wall and zero gamma are widely shared. Volatility Trigger, call resistance, put support and high volatility level are vendor-specific, so a level from one tool will not line up exactly with a similarly named level from another.
Where Each Tool Is Strongest
Rather than a ranking, which depends on how you trade, here is where each one earns its place.
- SpotGamma is one of the best-known names in GEX, with daily expert notes, real-time S&P 500 hedging tools and levels for 3,500+ stocks. It is the most complete package for SPX traders. It is also among the more expensive, and its fastest views are index-only.
- GEXBot is the fastest and cheapest real-time option at $50 a month, recomputing every second, with integrations for NinjaTrader and Sierra Chart and a 90-day archive. Coverage is limited to 56+ symbols, so it suits index and futures traders more than stock pickers.
- Volland covers about 4,500 symbols with 2-minute updates and a long list of second-order greek tools. Pricing starts at $150 and climbs steeply for the 0DTE and higher-order tools.
- Unusual Whales puts a real-time GEX heatmap for every U.S. symbol in its $50 plan alongside full options flow, which makes it strong value if you want flow and GEX together. Its fastest SPX exposure updates are on the $120 plan.
- MenthorQ suits traders who live in charting platforms: its levels feed TradingView, NinjaTrader and others, and it covers futures natively. Its pages say little about update speed or methodology.
- OptionCharts is the cheapest way to get call walls, put walls and the gamma flip, with a free single-expiration chart to try first. The $20 plan is 15 minutes delayed; real-time is $35.
- Cheddar Flow and Tradytics include GEX as one part of a broader flow platform, which is convenient if you already use them for options flow.
- Robinflow is the lowest-priced plan here with GEX on every optionable symbol, shown as a strike-by-expiration heatmap with walls and an estimated flip, alongside full options flow and dark pool data. It refreshes hourly for the most active symbols and before the open and after the close for the rest, so intraday and 0DTE traders who need minute-by-minute gamma are better served by GEXBot, Volland, SpotGamma or Unusual Whales.
Free GEX Data
| Source | What you get | Limits |
|---|---|---|
| SqueezeMetrics | Public chart of aggregate S&P 500 GEX, with history back to 2011 | Index-level only; full access is $720/mo by invitation |
| SpotGamma free SPX chart | Net gamma curve for SPX, "updated daily" | SPX only |
| OptionCharts free tier | GEX chart for one expiration at a time | Walls, flip and multiple expirations are paid |
| Robinflow symbol pages | Full GEX heatmap, walls and flip for the most active symbols, such as SPY and NVDA | 3 sessions delayed |
Free charts are enough to learn how GEX behaves and to check the regime on SPX. For single stocks, current walls and intraday changes, you will need a paid tool.
How We Tested
We read each vendor's public pricing, feature and help pages and recorded only what was stated there, and we recheck them as they change. Several sites only render in a normal browser and were read that way. Where a feature appears only in a vendor's API documentation, we say so. We did not subscribe to competitor products for this comparison, so we make no claims about the accuracy of their numbers beyond what they state themselves. ChartExchange and BlackBoxStocks also offer GEX charts inside broader plans ($35 and $79 a month), but their pages did not state update speed, coverage or methodology, so they are not in the table. If you are a vendor and something above is out of date, tell us and we will correct it.
How Robinflow Approaches This
The Robinflow GEX page renders gamma exposure as a heatmap across strike and expiration for every optionable U.S. symbol: gold for positive-gamma strikes that tend to pin price, purple for negative-gamma zones where moves can run, with spot marked against the grid. A summary strip gives the net figure, the top positive and negative strikes and an estimated flip, and the call and put walls stand out at a glance. A trading calendar lets you step back through earlier sessions.
We present GEX as an estimate built on open interest and standard dealer-positioning assumptions, next to options flow and dark pool levels rather than as a standalone signal, because the strikes that matter most are usually the ones where flow and positioning agree. If you are comparing flow and dark pool tools too, see our options flow scanner comparison and dark pool scanner comparison.
One plan includes everything (see pricing), and the 7-day free trial locks nothing.
Frequently Asked Questions
What is the best gamma exposure tool?
It depends on what you trade. For intraday SPX and futures, GEXBot updates every second for $50 a month and SpotGamma offers the most complete index package. For GEX across thousands of individual stocks, Volland, Unusual Whales and Robinflow cover the widest range, with Robinflow the lowest-priced. If you want GEX next to options flow in one plan, Unusual Whales and Robinflow both include it.
Is there a free GEX tool?
Yes, with limits. SqueezeMetrics publishes a free S&P 500 GEX chart with history back to 2011, SpotGamma a daily SPX gamma chart, and OptionCharts a single-expiration GEX chart. Robinflow's free symbol pages show the full heatmap and walls for the most active symbols, 3 sessions delayed.
How often is gamma exposure updated?
It depends on the tool. Open interest, the main input, is published once a day before the open, so every tool's structure changes overnight. Tools that recompute during the session with the latest price and volume range from every second to every few minutes; others publish one snapshot per session.
Why do different tools show different GEX levels?
Because each tool makes its own assumption about who holds each option. Open interest does not identify the holder, so tools assume dealers are long calls and short puts, or that market makers are on every trade, or classify each trade by where it printed. Different assumptions can move a wall or flip the sign of a strike. That is why it helps to use a tool that states its method.
What are call walls and put walls?
The strikes with the largest concentrations of positive gamma above and below the current price. Because dealer hedging leans against moves at those strikes, they often act as support or resistance and as magnets into expiration. They move as open interest changes, so recheck them each session.
How much does a GEX tool cost?
Plans that include GEX range from $19 to $150 a month in this comparison as of Oct 29, 2026, with professional and institutional tiers running from several hundred to thousands of dollars a month. Several tools also have a free tier or free chart.
