OpenAI: GPT-5.1-Codex-Mini

openai/gpt-5.1-codex-mini

GPT-5.1-Codex-Mini is OpenAI's budget option at $0.25/$2 per million input/output tokens, with a 400K-token context. It sits mid-board on capability, at #136 of 262 on the TryAii Score — its best showing is #20 on AIME-2025. It's reasonably quick at about 91 tokens/sec.

Prompt $/1M

$0.250

Completion $/1M

$2.000

Context

400,000 tok

Best provider

91 tok/s · Azure

Specs

Model id: openai/gpt-5.1-codex-mini
Display name: OpenAI: GPT-5.1-Codex-Mini
Modality: text+image->text
Tokenizer: GPT
Instruct type: —
Context length: 400,000
Max completion: 128,000
Prompt $/1M: $0.250
Completion $/1M: $2.000
Free tier: no

Capabilities

Function callingno
JSON modeno
System promptno
Visionno
Moderatedno

Benchmark scores

Each axis is one benchmark, normalized to the best model in the field.

No benchmark data for this model.

Speed by provider

Provider	tok/s	TTFT	Total latency
Azurefastest	91	4,433 ms	5,993 ms

Prompt caching by provider

Provider	Min tokens to cache	Notes
OpenAI	1,024 tokens	GPT-5.x pre-5.6: 90% cached-read discount, free cache writes. 5-10 min sliding TTL; extended retention up to 24h on eligible models (non-ZDR default since May 2026).