Does thinking count against the limit?
Yes. Thinking tokens are billed like output tokens.
Extended reasoning produces hidden tokens before the visible answer. Every vendor counts them against the same window as the answer itself, which is why a 'think harder' setting drains a session faster.
- Codex
- Reasoning effort high/xhigh multiplies usage; medium is the default.
- Claude Code
- Extended thinking is on by default for Opus; turn it off for routine edits.