Options data API cost calculator
Estimate request volume before comparing API plans. Most teams undercount selected-leg requests: chains are only the first pass, while quotes, trades, snapshots, and historical windows create the real request profile.
Daily requests
2,725
22-day month
59,950
Fit signal
Production candidate
Expiration and chain requests
25 expiration lookups and 600 chain requests make up the discovery layer.
Selected-leg depth
2,100 quote, trade, and snapshot requests come from contracts that pass first-stage filters.
Historical scale
Backtests multiply quickly across dates. Test a small representative window before committing to a full historical run.
| Request layer | What it measures | Cost-planning implication |
|---|---|---|
| Expiration discovery | One request per ticker to learn the listed dates before the workflow asks for chains or contracts. | Usually cheap, but it prevents expensive retries caused by invalid or holiday-adjusted dates. |
| Chain refreshes | Ticker count multiplied by selected expirations and refresh cadence during the trading day. | This is the dominant live-dashboard cost when many symbols refresh repeatedly. |
| Selected-contract depth | Quote windows, trade windows, and snapshot checks for contracts that pass the first filter. | This is where scanners and backtests usually underestimate volume. |
| Historical windows | Repeated quote, trade, or aggregate requests across dates, events, and selected OCC symbols. | Sample one representative period before scaling a full backtest or event study. |
Planning note
Build the request model from the workflow, not from a headline endpoint list
A chain scanner, quote-aware backtest, and live dashboard can all use the same API surface while creating very different request profiles. For a clean vendor comparison, write down how many underlyings, expirations, selected contracts, quote windows, trade windows, and snapshot checks you need on a normal production day.