GammaWins Calculator

We currently display 15-minute delayed data for all options and stock prices. For equity indices and stocks listed on the Norwegian exchange, the underlying value is derived from option prices, which may differ by a few cents at times.

We plan to introduce paid tiers with live data and direct index feeds from official providers. Sign up for our newsletter to get notified when it’s available.

We currently support equity and equity index options on US exchanges, as well as Danish, Swedish, and Norwegian equity and index options listed on Nasdaq Nordic.

We plan to expand coverage to additional equity markets, along with options on futures, currencies, and commodities. Sign up for our newsletter to get notified as we add new markets.

We use Black-Scholes for European options (mainly index options) and call options on stocks, and Bjerksund-Stensland for American put options.

Most other websites only use the Black-Scholes model, which can misprice American-style puts.

Our upcoming paid plan will add a third model that handles dividends more accurately. Black-Scholes and Bjerksund-Stensland assume dividends are paid as a steady rate, which isn’t realistic for many dividend-paying stocks. The new model will use a finite-difference approach to capture the real impact of dividend dates.

We currently assume a constant dividend rate based on recent payout history. This approach is consistent with the models we use and provides reasonable estimates for most stocks.

Our upcoming paid plan will introduce a more advanced model that uses exact ex-dividend dates to reflect how payouts affect option values in the real world. This will make pricing especially accurate for dividend-paying stocks near ex-dividend dates.

We use production-grade libraries that are widely used by trading firms including HFTs and market makers. These models are fast, stable, and proven in real-world conditions.

You can expect pricing and Greeks to be very close to fair value under typical market conditions.

You might see sharp changes in Greeks for American puts or options on dividend-paying stocks. This happens when early exercise becomes optimal — for example, near ex-dividend dates or deep in the money close to expiry.

In those regions, the option’s value can shift quickly, and Greeks like delta or theta reflect that with sudden changes. It’s not a bug — it’s how early exercise works.

Not yet. Traditional heatmaps for options can be hard to read and interpret. We're working on a better way to visualize prices by date and underlying price, something more intuitive and easier to use.

Sign up for our newsletter to get updates when it's available.

Yes — click the Share button above the option legs to generate a link you can revisit later. Shared links stay active for at least 90 days after their last use.

Shared links remain available for at least 90 days after they were last opened.

You're viewing a shared strategy that was created with older data. Since that historical data is no longer available in the app, we disable edits to ensure the results remain consistent with what was originally saved.

We're working on adding support for calculations based on historical data, which would allow full editing even for older links. Sign up for our newsletter to get updates when this is ready.

You can click the Share button to generate a link, then post it to our subreddit r/GammaWins. We'll do our best to reply, and others in the community may jump in as well.

Please send us an email with a screenshot and, if possible, a share link from the app (you can create one using the Share button above the option legs).

Thanks for helping us make GammaWins better!