Charm —
How Delta changes with the passage of time (Delta decay).
Quick Answer
Charm measures how much an option's Delta changes as one day passes — the 'Delta decay' that quietly re-shapes your directional exposure over time, especially near expiry.
Charm is one of the option Greeks — how Delta changes with the passage of time (Delta decay). OptionsGyan teaches the options fundamentals; the complete reference for Charm — the plain-English meaning, formula, original diagram, a worked Nifty example, common mistakes and FAQ — lives on GreeksGyan, our dedicated option-Greeks site.
Read the full Charm guide on GreeksGyan
Charm (—) — the full guide
Meaning, formula, diagram, Nifty worked example, misconceptions and FAQ.
All the option Greeks
Delta, Gamma, Theta, Vega, Rho and the second-order Greeks, in one reference.
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Published 1 July 2026. Educational content only — not investment advice.