Model Comparison

MiMo-V2.5-Pro vs o1-previewWhich is better in 2026?

Both models are evenly matched across the benchmarks. MiMo-V2.5-Pro is 48.3x cheaper per token.

Verdict: MiMo-V2.5-Pro vs o1-preview — which is better?

MiMo-V2.5-Pro (by Xiaomi) and o1-preview (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

MiMo-V2.5-Pro outperforms in 2 benchmarks (MATH, SWE-Bench Verified), while o1-preview is better at 2 benchmarks (GPQA, MMLU). Both models are evenly matched across the benchmarks.

On price, MiMo-V2.5-Pro is roughly 48.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

MiMo-V2.5-Pro also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose MiMo-V2.5-Pro if…

  • cost matters — it's about 48.3x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Apr 2026
  • you need open weights you can self-host or fine-tune

Choose o1-preview if…

  • you want predictable pricing at $15.00/M input and $60.00/M output

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

MiMo-V2.5-Pro outperforms in 2 benchmarks (MATH, SWE-Bench Verified), while o1-preview is better at 2 benchmarks (GPQA, MMLU).

Both models are evenly matched across the benchmarks.

Fri Jul 31 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

MiMo-V2.5-Pro costs less

For input processing, MiMo-V2.5-Pro ($0.43/1M tokens) is 34.5x cheaper than o1-preview ($15.00/1M tokens).

For output processing, MiMo-V2.5-Pro ($0.87/1M tokens) is 69.0x cheaper than o1-preview ($60.00/1M tokens).

In conclusion, o1-preview is more expensive than MiMo-V2.5-Pro.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Jul 31 2026 • llm-stats.com
Xiaomi
MiMo-V2.5-Pro
Input tokens$0.43
Output tokens$0.87
Best providerXiaomi
OpenAI
o1-preview
Input tokens$15.00
Output tokens$60.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

MiMo-V2.5-Pro accepts 1,048,576 input tokens compared to o1-preview's 128,000 tokens. MiMo-V2.5-Pro can generate longer responses up to 131,072 tokens, while o1-preview is limited to 32,768 tokens.

Xiaomi
MiMo-V2.5-Pro
Input1,048,576 tokens
Output131,072 tokens
OpenAI
o1-preview
Input128,000 tokens
Output32,768 tokens
Fri Jul 31 2026 • llm-stats.com

License

Usage and distribution terms

MiMo-V2.5-Pro is licensed under MIT, while o1-preview uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

MiMo-V2.5-Pro

MIT

Open weights

o1-preview

Proprietary

Closed source

Release Timeline

When each model was launched

MiMo-V2.5-Pro was released on 2026-04-27, while o1-preview was released on 2024-09-12.

MiMo-V2.5-Pro is 20 months newer than o1-preview.

MiMo-V2.5-Pro

Apr 27, 2026

3 months ago

1.6yr newer
o1-preview

Sep 12, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

MiMo-V2.5-Pro is available from Xiaomi, DeepInfra, Novita. o1-preview is available from OpenAI, Azure.

MiMo-V2.5-Pro

xiaomi logo
Xiaomi
Input Price:Input: $0.43/1MOutput Price:Output: $0.87/1M
deepinfra logo
Deepinfra
Input Price:Input: $1.00/1MOutput Price:Output: $3.00/1M
novita logo
Novita
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M

o1-preview

openai logo
OpenAI
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
azure logo
Azure
Input Price:Input: $16.50/1MOutput Price:Output: $66.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Xiaomi
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output tokens
Has open weights
Higher MATH score (86.2% vs 85.5%)
Higher SWE-Bench Verified score (78.9% vs 41.3%)
OpenAI
Higher GPQA score (73.3% vs 66.7%)
Higher MMLU score (90.8% vs 89.4%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against MiMo-V2.5-Pro and o1-preview side-by-side, then vote on the output you prefer.

MiMo-V2.5-Pro
✓ Preferred
o1-preview
Open in Playground
AI Model Comparison Table
Feature
Xiaomi
MiMo-V2.5-Pro
OpenAI
o1-preview

FAQ

Common questions about MiMo-V2.5-Pro vs o1-preview.

Which is better, MiMo-V2.5-Pro or o1-preview?

Both models are evenly matched across the benchmarks. MiMo-V2.5-Pro is made by Xiaomi and o1-preview is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does MiMo-V2.5-Pro compare to o1-preview in benchmarks?

MiMo-V2.5-Pro scores FrontierSWE (Impl.): 100.0%, GSM8k: 99.6%, ARC-C: 97.2%, MMLU-Redux: 92.8%, C-Eval: 91.5%. o1-preview scores MGSM: 90.8%, MMLU: 90.8%, MATH: 85.5%, GPQA: 73.3%, LiveBench: 52.3%.

Is MiMo-V2.5-Pro cheaper than o1-preview?

MiMo-V2.5-Pro is 34.5x cheaper for input tokens. MiMo-V2.5-Pro costs $0.43/M input and $0.87/M output via xiaomi. o1-preview costs $15.00/M input and $60.00/M output via openai.

What are the context window sizes for MiMo-V2.5-Pro and o1-preview?

MiMo-V2.5-Pro supports 1.0M tokens and o1-preview supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between MiMo-V2.5-Pro and o1-preview?

Key differences include context window (1.0M vs 128K), input pricing ($0.43 vs $15.00/M), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes MiMo-V2.5-Pro and o1-preview?

MiMo-V2.5-Pro is developed by Xiaomi and o1-preview is developed by OpenAI.

Related comparisons