One agent session
1M input tokens and 100K output tokens, no caching.
- Input1M x $30 = $30.00
- Output0.1M x $180 = $18.00
$48.00per session
OpenAI - Closed weights
GPT-5.5 Pro pricing and specs
GPT-5.5 Pro is a closed-weights model from OpenAI that costs $30 per 1M input tokens and $180 per 1M output tokens on the first-party API, with a 1.05M-token context window.
Last verified from developers.openai.com. All sources
- Input / 1M
- $30
- Output / 1M
- $180
- Context
- 1.05M tokens
- Weights
- Closed
Pricing per 1M tokens
| Item | Price / 1M tokens |
|---|---|
| InputPrompts up to 272,000 tokens | $30 |
| OutputPrompts up to 272,000 tokens | $180 |
| Batch inputBatch requests, prompts up to 272,000 tokens | $15 |
| Batch outputBatch requests, prompts up to 272,000 tokens | $90 |
| Long-context inputPrompts over 272,000 tokens | $60 |
| Long-context outputPrompts over 272,000 tokens | $270 |
Note: Priced by prompt length: a request with more than 272K input tokens pays the long-context pricing rates for the whole request (short context is <=272K input tokens). No cached-input discount. The pricing page lists no long-context Batch price, so those are blank. Responses API only. Regional processing adds 10%. Default snapshot gpt-5.5-pro-2026-04-23.
Specs
- Context window
- 1,050,000 tokens
- Max output
- 128,000 tokens
- Release date
- Provider
- OpenAI
- API model id
gpt-5.5-pro- Vercel AI Gateway id
openai/gpt-5.5-pro- Weights
- Closed weights
What GPT-5.5 Pro costs in practice
Worked from the standard list rates above, with the math shown so you can swap in your own token counts. These use the base rates, which apply while each request's prompt stays at or under 272,000 tokens; above that, GPT-5.5 Pro bills $60 input and $270 output for the whole request.
A chat app
10,000 requests a day at 2K input and 500 output tokens each.
- Input20M x $30 = $600.00
- Output5M x $180 = $900.00
$1,500.00per day
$45,000.00 per 30-day month
Compare with
| Model | Input / 1M | Output / 1M |
|---|---|---|
| GPT-5.5 Pro (this page) | $30 | $180 |
| GPT-5 ProOpenAI | $15 | $120 |
| o3-proOpenAI | $20 | $80 |
| GPT-5.6 CyberOpenAI | $12.50 | $75 |
| GPT-4OpenAI | $30 | $60 |
| o1OpenAI | $15 | $60 |
| GPT-6 AstraOpenAI | $10 | $50 |
Related reading
- Codex CLI 0.163: Instant Steering Is Now the DefaultCodex CLI 0.163.0 makes mid-response steering the default and adds searchable /config and a leader key. What changed and what to check before upgrading.
- Tool Calling Under the Hood: Claude Messages vs OpenAI ResponsesHow tool calling works on the wire: JSON schema tools, parallel calls, tool_choice, strict mode and streaming deltas in Claude Messages vs OpenAI Responses.
- Codex 'gpt-5.5 Model Is Not Supported' Error: The FixCodex says gpt-5.5 is not supported with a ChatGPT account because OpenAI retired it from ChatGPT sign-in on October 14. The fix and what still works.
- Codex CLI Background Daemon: How to Turn It OffCodex CLI starts a persistent, self-updating background daemon since 0.157.0. What it does, why it hit Hacker News and the reported workaround to turn it off.
- Codex CLI 0.162: Managed Worktrees and Pinned TasksCodex CLI 0.162 lets the agent create and list its own Git worktrees, adds pinned tasks and custom provider capability overrides. What to change this week.
- ChatGPT Free vs Go vs Plus After GPT-6: Which Model You GetFree and Go ($8) both get GPT-6 Luna in Chat. Plus ($20) is the cheapest plan with GPT-6 Sol and full Codex. What each ChatGPT plan buys now.
FAQ
How much does GPT-5.5 Pro cost per million tokens?
GPT-5.5 Pro costs $30 per 1M input tokens and $180 per 1M output tokens on OpenAI's first-party API, per developers.openai.com on October 17, 2026. Per 1M tokens, the batch rate is $15 input and $90 output. Prompts over 272,000 tokens are billed at $60 input and $270 output for the whole request.
What is GPT-5.5 Pro's context window?
GPT-5.5 Pro has a 1,050,000-token context window and returns up to 128,000 output tokens per response.
Are GPT-5.5 Pro's weights open?
No. GPT-5.5 Pro is a closed-weights model. You call it through OpenAI's API as gpt-5.5-pro or through Vercel AI Gateway as openai/gpt-5.5-pro.
When was GPT-5.5 Pro released?
OpenAI released GPT-5.5 Pro on April 24, 2026.
Sources
Last verified from developers.openai.com.
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