Seminal AI
§1

GPT-5.5 Pro

Maximum-compute single answers where being right beats being cheap (hard proofs, deep analysis).

Data checked 2026-09-06

OpenAI ga gpt-5.5-pro

Context window
1.1M tokens in
Max output
128K tokens out
Input
$30.00 per 1M tokens
Output
$180.00 per 1M tokens
Blended
$67.50 3:1 in:out
Knowledge cutoff
2025-12-01
Released
2026-04-24
Licence
proprietary

A What it is for

No cached-input discount at all, so avoid it for anything with a repeated prompt prefix.

At a three-to-one input-to-output ratio, GPT-5.5 Pro costs $67.50 per million tokens blended. A workload of one million input and 330,000 output tokens per day would run about $2682.00 per month at list price, before caching or batch discounts.

B Capabilities

tools vision reasoning batch structured-output web-search code-execution
Input modalitiestext, image
Output modalitiestext
Batch discount50% off asynchronous requests

C Others from OpenAI

Model Context Max out In $/M Out $/M Blended Status
GPT-6 Astra gpt-6-astra 1.1M 128K $10.00 $50.00 $20.00 ga
GPT-5.6 Sol gpt-5.6-sol 1.1M 128K $4.00 $20.00 $8.00 ga
GPT-5.6 Terra gpt-5.6-terra 1.1M 128K $2.00 $12.00 $4.50 ga
GPT-5.6 Luna gpt-5.6-luna 1.1M 128K $0.20 $1.20 $0.45 ga
GPT-5.6 Cyber gpt-5.6-cyber 400K 128K $12.50 $75.00 $28.13 ga
Daybreak Blue (alias) gpt-daybreak-blue-latest 1.1M 128K $4.00 $20.00 $8.00 ga
Daybreak Red (alias) gpt-daybreak-red-latest 400K 128K $12.50 $75.00 $28.13 ga
GPT-5.5 Cyber gpt-5.5-cyber $12.50 $75.00 $28.13 deprecated
GPT-5.5 gpt-5.5 1.1M 128K $5.00 $30.00 $11.25 ga
GPT-5.4 gpt-5.4 1.1M 128K $2.50 $15.00 $5.63 ga
GPT-5.4 Mini gpt-5.4-mini 400K 128K $0.75 $4.50 $1.69 ga
GPT-5.4 nano gpt-5.4-nano 400K 128K $0.20 $1.25 $0.46 ga

D Verify before you commit

Model pricing changes without notice and this page is a snapshot. Confirm against the vendor's own page before you build a budget on it.

Source: developers.openai.com · checked 2026-09-06 · OpenAI pricing · API docs