OpenAI

GPT-5.1-Codex-Mini

$0.25 per 1M input tokens and $2.00 per 1M output tokens · 400K context · vision, tools, reasoning, JSON.

Prices checked Oct 21, 2026 · tracked by LLM Cost Index since Oct 21, 2026

$0.25
input / 1M tokens
$2.00
output / 1M tokens
$0.03
cached input / 1M
400K
context window
128K
max output
20.4
Artificial Analysis intelligence index

What GPT-5.1-Codex-Mini costs per month

Estimated monthly bill for typical workloads, using the cached-input price for repeated context. Try your own numbers in the cost calculator.

WorkloadPer month
Customer chatbot
1,000 conversations a day, 8 turns each
$210
Document Q&A (RAG)
500 questions a day over retrieved documents
$35.52
Coding / tool-using agent
200 tasks a day, long tool-heavy contexts
$78.60
Content generation
30 long articles a day
$5.17
Classification / extraction
100,000 short items a day
$315

Price history

We started tracking GPT-5.1-Codex-Mini on Oct 21, 2026; the chart appears as soon as there is a second data point. See all recent price changes.

Cheaper alternatives to GPT-5.1-Codex-Mini

Models with the same tool calling, image input, structured output for at least 20% less (3:1 input/output mix), most capable first.

Cheaper alternatives to GPT-5.1-Codex-Mini
Model Input / 1M Output / 1M Context Capabilities
MiMo-V2.6-Pro
Xiaomi
$0.435 $0.87 1.05M visionaudiotoolsreasoningJSONopen weights
Claude Haiku 5.5
Anthropic
$0.10 $0.50 1M visiontoolsreasoningJSON
GLM 5.3 Flash
Z.ai
$0.041 $0.12 1.05M visiontoolsreasoningJSONopen weights
$0.30 $1.20 1.05M visiontoolsreasoningJSONopen weights
GPT-6 Luna
OpenAI
$0.10 $0.50 1.05M visiontoolsreasoningJSON

How to pay less for GPT-5.1-Codex-Mini

For a customer chatbot (1,000 conversations a day, 8 turns each) that costs $258 a month at list price without caching:

OptionPer monthYou save
Move to MiMo-V2.6-Pro (similar capabilities)$136$122 (47%)
Use prompt caching (60% of input cached)$210$47.52 (18%)

Other workloads: cut-your-bill tool for GPT-5.1-Codex-Mini.

Specifications

Model IDopenai/gpt-5.1-codex-mini
Inputimage, text
Outputtext
Tool callingYes
Structured outputYes
Reasoning modeYes
Open weightsNo
ReleasedNov 13, 2025
Web search$0.01 per request

FAQ

How much does GPT-5.1-Codex-Mini cost?
$0.25 per million input tokens and $2.00 per million output tokens; cached input costs $0.03 per million. Prices as of Oct 21, 2026.
What is the context window of GPT-5.1-Codex-Mini?
400K tokens, with up to 128K output tokens per response.
Does GPT-5.1-Codex-Mini support images, tools and structured output?
Images as input: yes. Tool calling: yes. Structured (JSON) output: yes. Reasoning mode: yes.
What are cheaper alternatives to GPT-5.1-Codex-Mini?
Models with the same key capabilities for at least 20% less include MiMo-V2.6-Pro ($0.435 / $0.87), Claude Haiku 5.5 ($0.10 / $0.50), GLM 5.3 Flash ($0.041 / $0.12).

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