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Grok-1.5 vs o3-mini

o3-mini leads the LLM Stats Score 21.8 to -2.0.

xAI · OpenAI · Updated for 2026

Which is better?

o3-mini leads the overall LLM Stats Score 21.8 to -2.0, ranking #169 overall.

In the 3 individual benchmarks reported for both models, o3-mini wins 3; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Grok-1.5

  • you are already invested in the xAI ecosystem

Choose o3-mini

  • overall performance matters — it scores 21.8 and ranks #169 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 3 of 3 exact shared results
  • you want the most recent training data — it shipped Jan 2025

At a glance

The differences that matter most.

Core performance indexes
-2.0
#317
21.8
#169
-1.5
#309
20.9
#169
-0.8
#228
5.3
#184
Cost, coverage & limits
Benchmark wins
0 of 3
3 of 3
Input price
— / M
$1.10 / M
Output price
— / M
$4.40 / M
Context window
200,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Grok-1.5
o3-mini
5.5#260
29.5#76
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

9 reported for Grok-1.5 · 25 for o3-mini

3 shared

Grok-1.5 outperforms in 0 benchmarks, while o3-mini is better at 3 benchmarks (GPQA, MATH, MMLU).

o3-mini significantly outperforms across most benchmarks.

Sun Aug 30 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only o3-mini specifies input context (200,000 tokens). Only o3-mini specifies output context (100,000 tokens).

xAI
Grok-1.5
Input- tokens
Output- tokens
OpenAI
o3-mini
Input200,000 tokens
Output100,000 tokens
Sun Aug 30 2026 • llm-stats.com

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Grok-1.5

Proprietary

Closed source

o3-mini

Proprietary

Closed source

Release Timeline

When each model was launched

Grok-1.5 was released on 2024-03-28, while o3-mini was released on 2025-01-30.

o3-mini is 10 months newer than Grok-1.5.

Grok-1.5

Mar 28, 2024

2.4 years ago

o3-mini

Jan 30, 2025

1.6 years ago

10mo newer

Knowledge Cutoff

When training data ends

o3-mini has a documented knowledge cutoff of 2023-09-30, while Grok-1.5's cutoff date is not specified.

We can confirm o3-mini's training data extends to 2023-09-30, but cannot make a direct comparison without Grok-1.5's cutoff date.

Grok-1.5

o3-mini

Sep 2023

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Grok-1.5 and o3-mini side-by-side, then vote on the output you prefer.

Grok-1.5
✓ Preferred
o3-mini
Open in Playground

FAQ

Common questions about Grok-1.5 vs o3-mini.

Which is better, Grok-1.5 or o3-mini?

o3-mini leads the LLM Stats Score 21.8 to -2.0. Grok-1.5 is made by xAI and o3-mini is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Grok-1.5 compare to o3-mini in benchmarks?

Grok-1.5 scores GSM8k: 90.0%, DocVQA: 85.6%, MMLU: 81.3%, HumanEval: 74.1%, MMMU: 53.6%. o3-mini scores COLLIE: 98.7%, MATH: 97.9%, IFEval: 93.9%, MGSM: 92.0%, AIME 2024: 87.3%.

What are the context window sizes for Grok-1.5 and o3-mini?

Grok-1.5 supports an unknown number of tokens and o3-mini supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok-1.5 and o3-mini?

Key differences include LLM Stats Score (-2.0 vs 21.8). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok-1.5 and o3-mini?

Grok-1.5 is developed by xAI and o3-mini is developed by OpenAI.