Last refreshed 2026-06-08. Next refresh: weekly.
Why use GPT-5.5 on OpenAI API?
OpenAI API offers GPT-5.5 with pay-as-you-go pricing at $5.00/1M input tokens. OpenAI is a leading AI research and deployment company dedicated to developing safe and beneficial artificial general intelligence (AGI) for humanity.
Compare GPT-5.5 across 3 providers to find the best fit for your use caseSetup recipe
Python + curlpip install openaiexport OPENAI_API_KEY=...import os
from openai import OpenAI
client = OpenAI() # reads OPENAI_API_KEY from env
response = client.chat.completions.create(gpt-5.5Request example
import os
from openai import OpenAI
client = OpenAI() # reads OPENAI_API_KEY from env
response = client.chat.completions.create(
model="gpt-5.5",
messages=[{"role": "user", "content": "Hello"}]
)
print(response.choices[0].message.content)Gotchas
- Use the model slug directly, e.g. "gpt-4o" or "gpt-4.1-mini".
- The examples expect OPENAI_API_KEY; rename it only if your application config maps the new variable.
Compare GPT-5.5 Across Providers
| Provider | Input (per 1M) | Output (per 1M) |
|---|---|---|
| OpenAI API | $5.00 | $30.00 |
| OpenRouter | $5.00 | $30.00 |
| Vercel AI Gateway | $5.00 | $30.00 |
Pricing
| Type | Price (per 1M) |
|---|---|
| Input tokens | $5.00 |
| Output tokens | $30.00 |
Capabilities
About GPT-5.5
GPT-5.5 is OpenAI's fully retrained agentic model, released April 23, 2026. Optimised for agentic coding, computer use, knowledge work, and early scientific research. Achieves 82.7% on Terminal-Bench 2.0 (Codex CLI scaffold), 84.9% on GDPval, 58.6% on SWE-Bench Pro, 93.6% on GPQA Diamond, and 82.6% on SWE-Bench Verified (Vals.ai independent harness). Knowledge cutoff December 2025. Supports reasoning effort levels (none/low/medium/high/xhigh). Context window 1,050,000 tokens with a long-context surcharge above 272K tokens. Model ID: gpt-5.5.
FAQ
What does GPT-5.5 cost on OpenAI API?
On OpenAI API, GPT-5.5 costs $5 per 1M input tokens and $30 per 1M output tokens.
What is the context window for GPT-5.5 on OpenAI API?
GPT-5.5 supports a 1.05m token context window on OpenAI API.
How does OpenAI API compare to other GPT-5.5 providers?
GPT-5.5 is available from 3 providers. The cheapest input pricing is $5/1M tokens from OpenAI API.
What API model ID do I use for GPT-5.5 on OpenAI API?
Use the model ID gpt-5.5 when calling OpenAI API's API.
Who created GPT-5.5?
GPT-5.5 was created by OpenAI as part of the GPT-5.5 model family.
Is GPT-5.5 open source?
GPT-5.5 is not open source; the seed data lists it as proprietary.