GPT-5 mini vs OpenAI o3

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

GPT-5 mini

OpenAI · Aug 2025

A fast, cheap distillation of GPT-5 for high-volume workloads — one fifth of the flagship's price with most of its everyday capability.

OpenAI o3

OpenAI · Apr 2025

68.9

OpenAI's dedicated 2025 reasoning model that pioneered thinking-with-images and agentic tool use within chain-of-thought.

The verdict

GPT-5 mini wins 2 of the 3 benchmarks these models share, against 1 for OpenAI o3. On price the gap is dramatic: GPT-5 mini works out roughly 5.1x cheaper per blended million tokens. GPT-5 mini also takes 400K of context versus 200K for OpenAI o3.

Benchmark head-to-head 21

SWE-bench Verified
~71%69.1%
GPT-5 miniOpenAI o3
GPQA Diamond
~82.3%83.3%
GPT-5 miniOpenAI o3
AIME 2025
~91.1%88.9%
GPT-5 miniOpenAI o3

Specs & pricing

GPT-5 miniOpenAI o3
modhub Index68.9
Input price / 1M$0.25$2
Output price / 1M$2$8
Context window400K200K
Max output128K100K
Open weightsnono
Reasoning modelyesyes
Multimodal inputtext, imagetext, image
Knowledge cutoffMay 2024May 2024
ReleasedAug 2025Apr 2025
Example monthly cost*$5.50$32.00

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, GPT-5 mini or OpenAI o3?
GPT-5 mini wins 2 of the 3 benchmarks these models share, against 1 for OpenAI o3. On price the gap is dramatic: GPT-5 mini works out roughly 5.1x cheaper per blended million tokens. GPT-5 mini also takes 400K of context versus 200K for OpenAI o3.
Which is cheaper, GPT-5 mini or OpenAI o3?
GPT-5 mini costs $0.25/$2 per million input/output tokens, while OpenAI o3 costs $2/$8. For a typical workload of 10M input and 1.5M output tokens per month, that's $5.50 versus $32.00.
Which model is better for coding, GPT-5 mini or OpenAI o3?
On SWE-bench Verified — the standard agentic-coding benchmark — GPT-5 mini scores ~71% versus 69.1% for OpenAI o3, making GPT-5 mini the stronger pick for coding agents.

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