Last refreshed 2026-05-19. Next refresh: weekly.
Why use GPT-5.5 Pro on OpenAI API?
OpenAI API offers GPT-5.5 Pro with pay-as-you-go pricing at $30.00/1M 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 Pro 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-5.5-proRequest example
import os
from openai import OpenAI
client = OpenAI() # reads OPENAI_API_KEY from env
response = client.chat.completions.create(
model="gpt-5.5-pro",
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 Pro Across Providers
| Provider | Input (per 1M) | Output (per 1M) |
|---|---|---|
| OpenAI API | $30.00 | $180.00 |
| OpenRouter | $30.00 | $180.00 |
| Vercel AI Gateway | $30.00 | $180.00 |
Pricing
| Type | Price (per 1M) |
|---|---|
| Input tokens | $30.00 |
| Output tokens | $180.00 |
Capabilities
About GPT-5.5 Pro
GPT-5.5 Pro is OpenAI's premium variant of GPT-5.5, released April 23, 2026. Targets large quality gains for business, legal, education, and data science use cases. Scores 39.6% on FrontierMath Tier 4 (postdoctoral-level math problems), compared to 22.9% for Claude Opus 4.7. Priced at 6× the standard GPT-5.5 API rate. Available to ChatGPT subscribers and via API.
FAQ
What does GPT-5.5 Pro cost on OpenAI API?
On OpenAI API, GPT-5.5 Pro costs $30.00 per 1M input tokens and $180.00 per 1M output tokens.
What is the context window for GPT-5.5 Pro on OpenAI API?
GPT-5.5 Pro supports a 1.05m token context window on OpenAI API.
How does OpenAI API compare to other GPT-5.5 Pro providers?
GPT-5.5 Pro is available from 3 providers. The cheapest input pricing is $30.00/1M tokens from OpenAI API.
What API model ID do I use for GPT-5.5 Pro on OpenAI API?
Use the model ID gpt-5.5-pro when calling OpenAI API's API.
Who created GPT-5.5 Pro?
GPT-5.5 Pro was created by OpenAI as part of the GPT-5.5 model family.
Is GPT-5.5 Pro open source?
GPT-5.5 Pro is not open source; the seed data lists it as proprietary.