Question 1

What is GPT-5.5 mini?

Accepted Answer

GPT-5.5 mini is a large language model from OpenAI, released on 15 March 2026. Production workhorse — GPT-5.5 quality reasoning at fast-tier prices.

Question 2

When was GPT-5.5 mini released?

Accepted Answer

GPT-5.5 mini was released by OpenAI on 15 March 2026.

Question 3

How much does GPT-5.5 mini cost?

Accepted Answer

GPT-5.5 mini costs $0.25 per 1 million input tokens and $1.00 per 1 million output tokens via OpenAI’s API. At a typical 3:1 input/output ratio the blended cost works out to about $0.44 per 1M tokens.

Question 4

How smart is GPT-5.5 mini?

Accepted Answer

GPT-5.5 mini scores 68 out of 100 on our intelligence index — a strong production-tier composite of MMLU, MMLU Pro, GPQA, MATH and HumanEval benchmark scores. That places it #11 of 22 language models we track.

Question 5

What is the context window of GPT-5.5 mini?

Accepted Answer

GPT-5.5 mini has a 400k-token context window — roughly 300,000 words of text. That’s what you can fit into a single request (your prompt plus all uploaded documents and the model’s response combined).

Question 6

What is GPT-5.5 mini best for?

Accepted Answer

GPT-5.5 mini is most useful for high-volume apis, chatbots and classification & extraction. Its key strengths are best $/token in openai lineup, very fast and 400k context.

Question 7

How fast is GPT-5.5 mini?

Accepted Answer

GPT-5.5 mini generates around 180 output tokens per second with a typical time-to-first-token of 280 ms on the major API providers. Reasoning models that "think" before answering will appear slower on tokens-per-second since they spend time on internal chain-of-thought.

Question 8

Is GPT-5.5 mini better than GPT-4o mini?

Accepted Answer

GPT-5.5 mini scores higher on our intelligence index (68 vs 56). On most general tasks GPT-5.5 mini has the edge — but GPT-4o mini can still be the better pick on cost or specific capabilities. See our full GPT-5.5 mini vs GPT-4o mini comparison at /ai-models/compare/gpt-5-5-mini-vs-gpt-4o-mini/.

Question 9

What is the best alternative to GPT-5.5 mini?

Accepted Answer

The closest alternatives to GPT-5.5 mini are GPT-4o mini, GPT-5.5 and GPT-4o. Each shares most of GPT-5.5 mini’s use-cases — pick by price, context window or specific capability rather than headline intelligence.

Question 10

Is GPT-5.5 mini open source?

Accepted Answer

No. GPT-5.5 mini is proprietary — the weights are not released. Access is via OpenAI’s own API and partner platforms. For open-weights alternatives in the same tier, see our open-source AI models page.

Question 11

Can I use GPT-5.5 mini for free?

Accepted Answer

The consumer ChatGPT product offers free, rate-limited access to a version of GPT-5.5 mini and DALL·E 3. The OpenAI API itself is paid — though new accounts get a small starting credit. Microsoft Copilot also bundles GPT access at no extra cost on some tiers.

GPT-5.5 mini

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