Context lengths are 1,050,000 tokens on gpt-5.5 and 1,050,000 tokens on gpt-5.5-free. Time to first token (TTFT) measured on AIHubMix is 4.0s on gpt-5.5 and 3.6s on gpt-5.5-free. Measured output throughput is 49.7 tok/s on gpt-5.5 and 42.0 tok/s on gpt-5.5-free.
gpt-5.5gpt-5.5-freeGPT-5.5 raises the baseline for complex production workflows. It’s a strong fit for coding use cases, tool-heavy agents, grounded assistants, long-context retrieval, product-spec-to-plan workflows, and customer-facing workflows where execution quality and response polish are critical.
This free model API comes from the OpenAI model deployed on Azure. To prevent abuse, the external content filter provided by Azure has been enforced, which will result in additional delays. If you want to experience the full version of the model API without filters, please use the paid version and request the model name ID without "-free". To maintain reliable service, each account is limited to 5 requests per minute, 500 requests per day, and 1 million tokens per day.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
gpt-5.5-free: 3.6s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
gpt-5.5 accepts 1,050,000 and gpt-5.5-free accepts 1,050,000 input tokens. Maximum output per request is 128,000 tokens on gpt-5.5 and 128,000 tokens on gpt-5.5-free.
gpt-5.5 at 49.7 tok/s and gpt-5.5-free at 42.0 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
gpt-5.5 accepts text and image input and supports thinking, function calling, structured outputs, web search and tool calling; gpt-5.5-free accepts text and image input and supports thinking, function calling, structured outputs, web search and tool calling.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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