Model Tracker

GPT-5.5

GPT-5.5 is an AI model made by OpenAI. OpenAI released it on 23 April 2026. It is generally available. It takes text, image and returns text.

In inglese

OpenAI

GPT-5.5 is an AI model made by OpenAI. OpenAI released it on 23 April 2026. It is generally available. It takes text, image and returns text. Its longest answer is 128,000 tokens. Its knowledge cutoff is 1 December 2025.

Released: 23 April 2026 — openai.com, read 19 October 2026
Status: Generally available — developers.openai.com, read 19 October 2026
Takes: Text, Image — developers.openai.com, read 19 October 2026
Returns: Text — developers.openai.com, read 19 October 2026
Open weights: Not confirmed: The maker's pages reviewed do not state whether GPT-5.5 weights are open or downloadable.
Licence: Not confirmed: The maker's pages reviewed do not name a model-weight licence for GPT-5.5.
Context window: Not confirmed: two readings disagree: 1050000 and 1000000
Longest answer: 128,000 tokens — developers.openai.com, read 19 October 2026
Knowledge cutoff: 1 December 2025 — developers.openai.com, read 19 October 2026
API price, input: Not confirmed: The current API pricing page does not list GPT-5.5. The model page displays a price, but the required standard-tier price from the pricing page is unconfirmed.
API price, output: Not confirmed: The current API pricing page does not list GPT-5.5. The model page displays a price, but the required standard-tier price from the pricing page is unconfirmed.
Where: Not confirmed: two readings disagree: api and api, app
Parameters: Not confirmed: The maker's pages reviewed do not publish a parameter count for GPT-5.5.
Model card: https://deploymentsafety.openai.com/gpt-5-5/gpt-5-5.pdf — deploymentsafety.openai.com, read 19 October 2026

Benchmarks

Measured by others, not by the maker: each score with the name the measurer gives the model and the setting it ran, its day and its licence.

Arena

Text Arena, gpt-5.5-high: 1,481 (1,478–1,485, 69,401 votes), published 15 October 2026
Text Arena, gpt-5.5: 1,477 (1,473–1,480, 70,985 votes), published 15 October 2026
Vision Arena, gpt-5.5: 1,286 (1,280–1,292, 27,993 votes), published 9 October 2026
Vision Arena, gpt-5.5-high: 1,281 (1,275–1,287, 26,281 votes), published 9 October 2026

Arena’s leaderboard dataset (lmarena-ai/leaderboard-dataset on Hugging Face), CC BY 4.0: ratings from people’s votes between two anonymous models, as Arena publishes them. Data · CC BY 4.0

Epoch AI

Epoch Capabilities Index, GPT-5.5: 159.0 (156.4–161.9), as of 19 October 2026
GPQA Diamond, gpt-5.5-pre-release_xhigh: 94.0% (± 1.5), run 24 April 2026
GPQA Diamond, gpt-5.5_low: 90.7% (± 1.8), run 5 May 2026
GPQA Diamond, gpt-5.5_none: 77.3% (± 3.0), run 7 August 2026
FrontierMath, tiers 1–3, gpt-5.5_xhigh: 85.3% (± 2.1), run 11 June 2026
FrontierMath, tier 4, gpt-5.5_xhigh: 72.5% (± 7.1), run 11 June 2026
SWE-bench Verified, gpt-5.5-pre-release_xhigh: 80.6% (± 1.8), run 24 April 2026
OTIS Mock AIME 2024–2025, gpt-5.5-pre-release_xhigh: 100.0% (± 0.0), run 24 April 2026
OTIS Mock AIME 2024–2025, gpt-5.5_low: 84.4% (± 5.5), run 7 August 2026
OTIS Mock AIME 2024–2025, gpt-5.5_none: 57.8% (± 7.4), run 7 August 2026
SimpleQA Verified, gpt-5.5_xhigh: 63.0% (± 1.5), run 27 August 2026

Epoch AI, ‘Capabilities & benchmarking’, epoch.ai/benchmarks, CC BY 4.0: Epoch AI’s own runs and its Capabilities Index. Data · CC BY 4.0

Questions

When was GPT-5.5 released?

OpenAI released GPT-5.5 on 23 April 2026.

Is GPT-5.5 still available?

Yes: it is generally available, as OpenAI states it.

What does GPT-5.5 take and return?

GPT-5.5 takes text, image and returns text.

What is the knowledge cutoff of GPT-5.5?

The knowledge cutoff of GPT-5.5 is 1 December 2025.

Sources

GPT-5.5 Model | OpenAI API (read 19 October 2026)
Introducing GPT-5.5 (read 19 October 2026)
Model Release Notes (read 19 October 2026)
GPT-5.5 System Card (read 19 October 2026)

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