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GPT 5.1 Thinking API price

Name: GPT 5.1 Thinking
Brand: OpenAI

OpenAI · 400K token context · 2 sellers, checked 26 Oct, 00:17 UTC

Input, per 1M tokens

$1.25

Output, per 1M tokens

$10.00

Cheapest at Cheaper Inference; 2 sellers compared below.

The only price here comes from Cheaper Inference, a seller we have not verified (our read). Test it on your own prompts before you rely on it.

Cost calculator: where to buy, and what it costs you

Pick a use case, a volume and a provider. Monthly figures assume 30 days.

1,500 input and 400 output tokens per request, 30% of input cached.

Requests per day

Provider, with its monthly cost for this workload

Cheaper Inference ↗Discount marketplace · not verified by easiapiai$1.25 in · $10.00 out · cached $0.13 per 1M$161Cheapest
Vercel AI Gateway ↗Gateway · not verified by easiapiai$1.25 in · $10.00 out · cached $0.13 per 1M$161Not verified by us

Spotted a wrong or outdated price? Report it and we fix it at the next update.

Test a seller of this model with your own key, on your own machine.

Cheapest standard price per 1M tokens, recorded every 6 hours since 16 Oct 2026.

OutputInput

24 Oct Cheaper Inference raised input $0.81 to $1.25 (+54%), output $6.50 to $10.00 (+54%)
20 Oct Cheaper Inference first listed in our data at $0.81 / $6.50
20 Oct Vercel AI Gateway first listed in our data at $1.25 / $10.00

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