GPT-5.5 Pro
OpenAI · Frontier
Highest-accuracy reasoning variant of GPT-5.5.
- Strengths
- OpenAI's highest-accuracy reasoning variant.
- Best for
- Mission-critical analysis where answer quality outweighs latency and cost.
- Limitations
- Slowest and priciest GPT-5.5 tier; wasteful for simple prompts.
Input / 1M
$30.00
Output / 1M
$180.00
Cached input / 1M
—
Context window
1M
Where it sits
24th-cheapest frontier model
by blended $/Mtok among 24 listed frontier models
1762% above the frontier median
blended $/Mtok across 24 frontier models
Output costs 6× input
$30.00 in / $180.00 out per 1M
Held flat since launch (Apr 2026)
no blended price change recorded
Computed live from current prices and this model's history — not hand-written, so it stays accurate as prices move.
Price history
Only one price on record so far — the history chart appears once a price changes.
Snapshots
| Effective | Input | Output | Cached in | Note | Source |
|---|---|---|---|---|---|
| 24 Apr 2026 | $30.00 | $180.00 | — | openai.com/api/pricing |