Standard OCC option symbol format
A compact option identifier contains a root symbol, six-digit expiration date, one character for call or put and an eight-digit strike field. For example, SPY260116C00600000 represents a SPY call expiring January 16, 2026 with a $600 strike.
The expiration uses YYMMDD. C identifies a call and P identifies a put. The strike field stores the price multiplied by 1,000 and padded to eight digits, so 00600000 becomes 600.000.
Why option roots can look unusual
The option root is not always identical to the familiar stock ticker. Corporate actions, adjusted contracts, minis and class shares can produce roots or deliverables that require the official contract specification. A syntactically valid symbol does not prove that the contract exists or has a standard 100-share deliverable.
Some data APIs prepend O: to distinguish option tickers from stocks. The decoder accepts that prefix and removes spaces before parsing.
- Root: one to six letters or digits in the compact identifier.
- Expiration: YYMMDD.
- Side: C for call or P for put.
- Strike: eight digits representing thousandths of a dollar.
Always verify adjusted contracts
A merger, split, spin-off or special distribution can change an option’s deliverable while its compact symbol still resembles a standard contract. The strike alone cannot describe cash components or adjusted share quantities.
Use this decoder for readability, then verify the contract with your broker or the official option contract memo before trading, exercising or estimating assignment exposure.