OpenAI · Released 2025-08-07

GPT-5 Mini

Available
gpt-5-mini

Call gpt-5-mini on Lazu for $0.25 per million input tokens and $2.00 per million output tokens, the same as the OpenAI official price. 272k context, up to 128k output tokens, with Tool calling, Vision, Reasoning and Structured output.

GPT-5 Mini is a compact version of GPT-5, designed to handle lighter-weight reasoning tasks. It provides the same instruction-following and safety-tuning benefits as GPT-5, but with reduced latency and cost....

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Context272k
Max output128k
Knowledge cutoff2024-05
InputText · Image
OutputText
Endpoints/v1/chat/completions · /v1/responses

Prices and lanes

USD per million tokens. Availability covers the last 7 days, 2 hours per bar.

Lane InputOutputCache readCache write 5m 7-day availability
OpenAI official price $0.25 $2.00$0.025— —
Stable Same as official $0.25 $2.00—— 96.6%

Prices checked 2026-10-03 16:41 UTC · How to choose a lane · gpt-5-mini.json · gpt-5-mini.md

Capabilities

Tool callingVisionReasoningStructured outputPDF inputWeb search
Reasoning effort
minimal · low · medium · high
Unsupported parameters
temperature — leave it out of the request; this model does not accept it

Example request

POST /v1/chat/completions
curl -X POST https://api.lazu.ai/v1/chat/completions \
  -H "Authorization: Bearer $LAZU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5-mini",
    "messages": [{ "role": "user", "content": "Hello from Lazu" }]
  }'

Any OpenAI SDK works too: set base_url to https://api.lazu.ai/v1. Full integration docs

Questions

What is the difference between the stable and discount lanes?

The stable lane runs on each maker's official API, is billed at the list price, has the highest availability and suits every use. The discount lane is a reverse-engineered route: a third-party supplier serves the model through its official client, not the official API. It costs far less, but availability varies, a failed request does not fall back to the stable lane, and the supplier may add its own system prompt. So use it only inside the matching agent tool: Claude models in Claude Code, GPT models in Codex, Gemini models in Antigravity. For your own code, or anywhere the output must be controlled exactly, use the stable lane. Both lanes work with the same key, and each key picks the lane per model.

Can I call gpt-5-mini with the OpenAI SDK?

Yes. Point the SDK's base URL at https://api.lazu.ai/v1 and use gpt-5-mini as the model name.

How is it billed?

Per token actually used — input, output and cache — deducted from your wallet balance. There is no monthly fee, and every request shows up itemized in your usage log.

Same family

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