GPT-5.5
GPT-5.5 is a GPT-5 model from OpenAI, released in 2026-04. It costs $5 / $30 per 1M, has a 1.1M-token context window, and is best for coding, agents, complex-reasoning. Last verified 2026-04-27.
Spec sheet
Pricing
- Input
- $5 / 1M
- Output
- $30 / 1M
- Cached input
- $0.5 / 1M
- Batch discount
- 50%
- Free tier
- No
Context & speed
- Context window
- 1.1M tokens
- Max output
- 128k tokens
- Throughput
- ~100 tok/s
- Time to first token
- ~600 ms
- Speed tier
- balanced
Capabilities
- Tool use
- Yes
- Structured output
- Yes
- Prompt caching
- Yes
- Extended thinking
- Yes
- Vision input
- Yes
- Audio in / out
- No
- Fine-tuning
- No
Deployment
- Open weights
- No
- On-prem
- No
- HIPAA eligible
- Yes
- Zero retention
- Yes
- Regions
- us, eu
Estimated monthly cost
Assumes typical token shape: 2k input, 600 output per call. Prompt caching is excluded from these figures.
When to use GPT-5.5
Sweet spot
- coding
- agents
- complex reasoning
- long context
- general production
Known trade-offs
- 2x more expensive than GPT-5.4
- tokens above 272K incur 2x input / 1.5x output charges
Works with
Compare GPT-5.5 to other models
FAQ — GPT-5.5
How much does GPT-5.5 cost?
GPT-5.5 costs $5 / $30 per 1M tokens on the OpenAI API. Cached input reads cost $0.5 per 1M, cutting the input bill by roughly 90% on repeat system prompts. The batch API offers a 50% discount for async workloads.
What is the context window of GPT-5.5?
GPT-5.5 has a 1.1M-token context window with up to 128k tokens of output. That's enough for entire codebases, long transcripts, or multi-document RAG.
Does GPT-5.5 have a free tier?
No — Paid-only — no free API tier; available via ChatGPT Plus/Pro.
Is GPT-5.5 HIPAA / EU / on-prem friendly?
GPT-5.5 is HIPAA-eligible, available in EU regions, and is API-only. Zero data retention is available for enterprise customers.
What is GPT-5.5 best for?
GPT-5.5 is best for coding, agents, complex reasoning, long context. Trade-offs to be aware of: 2x more expensive than GPT-5.4; tokens above 272K incur 2x input / 1.5x output charges.
Which tools and SDKs work with GPT-5.5?
GPT-5.5 integrates with OpenAI SDK, Azure OpenAI, Cursor, Vercel AI SDK, LangChain, LlamaIndex, OpenRouter. Most major AI frameworks support it either natively or through OpenAI-compatible endpoints.