GPT-5.5
OpenAI's previous flagship, retired in favour of GPT-5.6 Terra — the same AA Intelligence Index v4.1 score of 55 at half the token price.
Start requirement: From 1 credit
GPT-5.5 has been retired. It can no longer be selected for new runs, and past runs that used it stay viewable. The specs below are kept for reference.
Capabilities
Pricing
| Up to 272K prompt tokens · Input | $5.75 / 1M tokens |
| Up to 272K prompt tokens · Cached input | $0.575 / 1M tokens |
| Up to 272K prompt tokens · Output | $34.5 / 1M tokens |
| Over 272K prompt tokens · Input | $11.5 / 1M tokens |
| Over 272K prompt tokens · Cached input | $1.15 / 1M tokens |
| Over 272K prompt tokens · Output | $51.75 / 1M tokens |
| Web search (when used) | $11.5 / 1,000 calls |
List prices plus 15%. Higher reasoning effort can consume more output tokens; it has no separate fixed multiplier. One credit equals 1¢ charged, with a one-credit minimum per completed run and the aggregate rounded up once.
Provider pricing source · verified 2026-07-20
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