Max pain
Also called maximum pain, pin strike
Max pain is the strike at which the largest total value of open options would expire worthless.
In more detail
It is computed by walking every strike and summing what all open calls and puts would be worth if the underlying settled there. The strike where that total is smallest is max pain.
The theory attached to it — that price gravitates toward this strike into expiry — is contested and the evidence is mixed. It is more defensible as a description of where option value is concentrated than as a prediction of where price will settle.
How Hermes measures it
Hermes reports max pain per expiry from open interest and strike data on the ticker pages and in the in-app open interest panel.
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