The Known Good Updated 25 Jul 2026
Google: Gemini 2.5 Pro vs OpenAI: o3 Mini ·Google vs OpenAI

Google: Gemini 2.5 Pro vs OpenAI: o3 Mini — head-to-head comparison

Google: Gemini 2.5 Pro profile OpenAI: o3 Mini profile All comparisons
Google: Gemini 2.5 Pro — Google
Quality
#29 of 61
64based on 4 of 6 evaluations
Known Good Index
Speed
#53 of 316
96.5
Output tokens per second
Price
#262 of 340
$3.44
Blended per 1M tokens
In $1.25 · Out $10.00
Cache hit price
#106 of 206
$0.12
per 1M tokens (−90%)
Context
#29 of 345
1.05M
tokens (~1,600 pages)
OpenAI: o3 Mini — OpenAI
Quality
#15 of 61
82based on 3 of 6 evaluations
Known Good Index
Speed
#23 of 316
131.4
Output tokens per second
Price
#236 of 340
$1.93
Blended per 1M tokens
In $1.10 · Out $4.40
Cache hit price
#189 of 206
$0.55
per 1M tokens (−50%)
Context
#205 of 345
200k
tokens (~300 pages)
Summary

On the Known Good Index, Google: Gemini 2.5 Pro scores 64 and OpenAI: o3 Mini scores 82 — a 17-point lead for OpenAI: o3 Mini. They share 2 published evaluations, with Google: Gemini 2.5 Pro ahead on 2 and OpenAI: o3 Mini ahead on 0.

Blended pricing is $3.44 per 1M tokens for Google: Gemini 2.5 Pro and $1.93 for OpenAI: o3 Mini — OpenAI: o3 Mini is about 1.8× cheaper.

Throughput is 96 tokens per second for Google: Gemini 2.5 Pro and 131 for OpenAI: o3 Mini, with time to first token at 5.3s and 3.1s. Google: Gemini 2.5 Pro accepts 1.05M tokens of context against 200k.

Google: Gemini 2.5 Pro is proprietary; OpenAI: o3 Mini is proprietary. 3 tracked hosts serve one or both.

Generated from tracked data on 26 Jul 2026 · how these comparisons are computed →

At a glance
MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Known Good Index 64 based on 4 of 6 evaluations 82 based on 3 of 6 evaluations
Blended $/1M $3.44 $1.93
Output tok/s 96 131
Context window 1.05M 200k
Providers 2 1
Jump to section

Quality

Known Good Index and the capability indices, side by side

IndicesComponents
Index scores

Each index is min-max normalised across tracked models and scaled 0–100 from published evaluations. We do not run these evaluations.

MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Known Good Index 64 82
Coding Index 42 —
Mathematics Index 84 88
Science Index 89 78
Reasoning Index — 85
Agentic Index 42 —
Openness Index 5 5
The Known Good

Quality Breakdown

Every evaluation both models report a published score for

Evaluations both models report

Bar = Google: Gemini 2.5 Pro · marker = OpenAI: o3 Mini · scores ingested from Epoch AI (CC-BY 4.0)

GPQA Diamond85 / 77
MATH / AIME84 / 77

Right-hand figures read Google: Gemini 2.5 Pro / OpenAI: o3 Mini. Google: Gemini 2.5 Pro leads on 2 of 2, OpenAI: o3 Mini on 0.

The Known Good

Arena Elo

Human preference rating from blind pairwise votes

Arena ratings

Elo from blind pairwise votes, ingested from Arena. Higher is better.

MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Text Arena 1,457 1,319
Text Arena (style controlled) 1,446 1,348
The Known Good

Price & Cost

Published API pricing by token type

Per token typeCache discount
Published pricing

USD per 1M tokens. Blended is a 3:1 input:output mix. Live from OpenRouter, cross-checked against models.dev. Lower is better.

MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Input $/1M $1.25 $1.10
Output $/1M $10.00 $4.40
Blended $/1M $3.44 $1.93
Cache read $/1M $0.125 $0.550
The Known Good
We publish blended price rather than cost-per-task. Cost-per-task requires token counts from an evaluation suite we do not run. Blended price is computed from published rates and is fully reproducible — see the pricing methodology.

Context Window

Maximum input accepted and maximum output emitted

Context and output limits

Provider-declared limits, from metadata via models.dev and OpenRouter. Higher is better.

MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Context window 1.05M 200k
Max output tokens 66k 100k
The Known Good

Speed & Latency

Median throughput and time to first token across hosting providers

Output speedTime to first token
Throughput and latency

Medians across all tracked providers, derived from OpenRouter endpoint telemetry.

MetricGoogle: Gemini 2.5 ProOpenAI: o3 Mini
Output tokens/s 96 131
Time to first token 5.3s 3.1s
The Known Good

Providers

Which hosts serve each model, and at what price and speed

3 hosts
Full provider benchmarks →
Provider Google: Gemini 2.5 Pro blendedGoogle: Gemini 2.5 Pro tok/s OpenAI: o3 Mini blendedOpenAI: o3 Mini tok/s
Google AI Studio $1.72 106 — —
Google · first party $1.72 93 — —
OpenAI · first party — — $1.93 123

Per-host pricing and telemetry from OpenRouter. A dash means that host does not serve that model.

The Known Good
Sources for this page
Pricing & providers — OpenRouter Metadata — models.dev Benchmarks — Epoch AI (CC-BY 4.0)Elo — Arena Full attribution →