OpenAI · Model
GPT-5.5 pricing, context window and specs
GPT-5.5 costs $5 per million input tokens and $30 per million output tokens, and reads up to 1,050,000 tokens per request. By blended price it is number 8 of OpenAI’s 10 current models here, counting from the cheapest.
- Input / 1M
- $5
- Output / 1M
- $30
- Cached / 1M
- $0.50
- Context
- 1,050,000
- Max output
- 128,000
- Released
- 2026-04-24
Estimate your cost with GPT-5.5Compare all OpenAI modelsCount tokens for GPT-5.5
Pricing
GPT-5.5 API pricing
| Price per 1M tokens | Input | Output |
|---|---|---|
| Standard | $5 | $30 |
| Cached input (read) | $0.50 | – |
| Batch API | $2.50 | $15 |
| Prompts of 272,000+ tokens | $10 | $45 |
Output costs 6.0× the input price, so long replies drive the bill more than long prompts. If your requests share a long fixed prefix, such as a system prompt or tool definitions, caching cuts that part to 10% of the normal input price. Once a single prompt reaches 272,000 tokens, the whole request is billed at the higher long-context rate shown above.
Examples
What GPT-5.5 costs in practice
| Workload | Tokens in / out | Requests/day | Per request | Per month |
|---|---|---|---|---|
| Support chatbot50% cached | 1,500 / 400 | 1,000 | $0.0161 | $490.47 |
| RAG app20% cached | 6,000 / 500 | 500 | $0.0396 | $602.25 |
| Coding agent80% cached | 40,000 / 2,000 | 200 | $0.12 | $705.67 |
| Document summariserbatch | 8,000 / 600 | 300 | $0.029 | $264.63 |
Change any number in the cost calculator.
Context
Context window
GPT-5.5 accepts up to 1,050,000 tokens per request, roughly 787,500 English words or 1,575 pages. That budget is shared between your prompt and the reply, and a single reply is capped at 128,000 tokens.
Filling the whole window with one prompt costs about $10.50 at list price, so for repeated long-document work, retrieval (sending only the relevant parts) or prompt caching is usually much cheaper.
Features
Capabilities
- Image input
- Yes
- Tool / function calling
- Yes
- Reasoning mode
- Yes
- Prompt caching
- Yes
- Structured output
- Yes
- Open weights
- No
- Accepts
- file, image, text
- Knowledge cutoff
- 2025-12-01
As declared by the provider’s API. It shows a feature exists, not how well it works.
API
GPT-5.5 model ID
- OpenRouter
openai/gpt-5.5- OpenAI API
gpt-5.5(alias)gpt-5.5-2026-04-23(pinned)
OpenAI lists GPT-5.5 as current. Every GPT model ID, with aliases and snapshots.
OpenAI
Where GPT-5.5 sits in OpenAI’s line-up
Ranked by blended price (three parts input to one part output, $11.25 per 1M for GPT-5.5), it is number 8 of OpenAI’s 10 current models here, counting from the cheapest. One step down, GPT-5.6 Terra costs $4.50 blended (60% less). It has the same published limits and features as GPT-5.5. One step up, GPT-6 Astra costs $20 (1.8× as much). It has the same published limits and features as GPT-5.5. See every OpenAI model and price
| Model | Input / 1M | Output / 1M | Context | Released |
|---|---|---|---|---|
| gpt-oss-120b | $0.037 | $0.17 | 131,072 | 2025-08-05 |
| GPT-6 Luna | $0.10 | $0.50 | 1,050,000 | 2026-09-22 |
| GPT-4o-mini | $0.15 | $0.60 | 128,000 | 2024-07-18 |
| GPT-5.4 Mini | $0.75 | $4.50 | 400,000 | 2026-03-17 |
| GPT-6.1 Sol | $2 | $10 | 1,050,000 | 2026-09-29 |
| GPT-4o | $2.50 | $10 | 128,000 | 2024-05-13 |
| GPT-5.6 Terra | $2 | $12 | 1,050,000 | 2026-07-09 |
| GPT-5.5 (this page) | $5 | $30 | 1,050,000 | 2026-04-24 |
| GPT-6 Astra | $10 | $50 | 1,050,000 | 2026-09-04 |
| GPT-5.5 Pro | $30 | $180 | 1,050,000 | 2026-04-24 |
OpenAI’s current models with a page here, cheapest first. Older and superseded models are listed on the provider page and in the comparison table.
History
Earlier versions of GPT-5.5
The previous model in this line is GPT-5.4, first listed on 2026-03-05. Compared with it, GPT-5.5’s input price is 100% higher and its output price is 100% higher.
| Model | Input / 1M | Output / 1M | Context | Released |
|---|---|---|---|---|
| GPT-5.4 | $2.50 | $15 | 1,050,000 | 2026-03-05 |
| GPT-5.2 | $1.75 | $14 | 400,000 | 2025-12-10 |
| GPT-5.1 | $1.25 | $10 | 400,000 | 2025-11-13 |
| GPT-5 | $1.25 | $10 | 400,000 | 2025-08-07 |
| GPT-4.1 | $2 | $8 | 1,047,576 | 2025-04-14 |
Earlier releases with the same name and size in our data, newest first. Dates are when our source first listed each model.
Save
Cheaper alternatives
- Seed-2.0-CodeByteDance Seed90% cheaper
- Gemini 3.8 FlashGoogle87% cheaper
- GPT-5.4 MiniOpenAI85% cheaper
- GLM 5V TurboZ.ai83% cheaper
- Qwen3.8 Max (0902)Qwen73% cheaper
Current models from major providers, one per provider, that keep image input, tool calling, a reasoning mode, a usable context window and output limit. Compared by blended price.
Compare
Similarly priced models
- Claude Opus 5.5Anthropic$4 / $20
- Qwen3.8 Max PrimeQwen$4 / $12
- Nova Premier 1.0Amazon$2.50 / $12.50
- Gemini 3.1 Pro PreviewGoogle$2 / $12
- GLM 5.3 PrimeZ.ai$2.80 / $8.80
Current models from other major providers, closest blended price.
FAQ
GPT-5.5 questions
How much does GPT-5.5 cost?
GPT-5.5 costs $5 per million input tokens and $30 per million output tokens, with cached input at $0.50. A typical chatbot reply (1,500 tokens in, 400 out) costs about $0.0195. Use the LLM cost calculator for your own workload.
What is GPT-5.5’s context window?
1,050,000 tokens, about 787,500 English words or 1,575 printed pages, shared between your prompt and the reply. A single reply can be up to 128,000 tokens.
Does GPT-5.5 support prompt caching and batch requests?
Yes, cached input is billed at $0.50 per million tokens (10% of the normal input price). A batch API is available at $2.50 input and $15 output per million tokens.
What are cheaper alternatives to GPT-5.5?
With the same essentials (image input and tool calling), the cheapest options are Seed-2.0-Code (90% cheaper), Gemini 3.8 Flash (87% cheaper), GPT-5.4 Mini (85% cheaper). Cheaper doesn’t mean equivalent, so test them on your own prompts.
What is the API model ID for GPT-5.5?
On OpenRouter it is openai/gpt-5.5. In OpenAI’s own API, use gpt-5.5; OpenAI lists the model as current. The GPT model ID list has every alias and snapshot. Pass the ID as the model value in each request.
What did GPT-5.5 replace?
The previous OpenAI model in the same line is GPT-5.4, first listed on 2026-03-05. Compared with it, GPT-5.5’s input price is 100% higher and its output price is 100% higher. Prices are only part of the picture, so test the newer model on your own prompts before switching.
Is GPT-5.5 open source?
No, GPT-5.5 is only available through OpenAI’s API and partners; its weights aren’t published.