Skip to main content
Joyride publishes a model price, a mark implied volatility, and per-unit Greeks for every listed instrument. The app’s options chain, the Chance of Profit and Leverage columns, and the API all read the same values.

​
Where the numbers come from

The mark implied volatility comes from a continuously refreshed volatility surface for the underlying. The model price is the Black-76 value at that IV, with the forward equal to spot and a zero rate. Every price and Greek Joyride shows, on the chain, on the position cards, and on the charts, uses this same model and convention. Margin and liquidation do not use the model price. They use a separate mark price that arrives with the same price feed and is read directly by the risk engine. The two are usually close, since both come from the same volatility surface, but they are not the same number, and the mark price used for margin is not published.

​
The fields

​
Option price charts

The price chart on an instrument’s screen is a modeled series, not a record of past trades or past marks. Each point is the Black-76 value of the option at that moment’s spot price, the strike, the time then remaining to expiry, and the instrument’s current mark IV. Spot history comes from the underlying’s price feed; the IV is today’s, applied across the whole series. The line therefore shows how the option’s value would have tracked the underlying at the current volatility, and it is recomputed when the mark IV moves. Until an instrument has a mark IV, the chart falls back to the midpoint of any quotes it has received, or stays empty.