Model Comparison
GPT-5.5 vs MiMo-V2.5-ProWhich is better in 2026?
GPT-5.5 significantly outperforms across most benchmarks. MiMo-V2.5-Pro is 20.7x cheaper per token.
Verdict: GPT-5.5 vs MiMo-V2.5-Pro — which is better?
GPT-5.5 (by OpenAI) and MiMo-V2.5-Pro (by Xiaomi) 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.
GPT-5.5 outperforms in 5 benchmarks (Finance Agent v2, GPQA, Humanity's Last Exam, SWE-Bench Pro, Terminal-Bench 2.0), while MiMo-V2.5-Pro is better at 1 benchmark (GDPval-AA). GPT-5.5 significantly outperforms across most benchmarks.
On price, MiMo-V2.5-Pro is roughly 20.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose GPT-5.5 if…
- you want the strongest raw capability — it leads on 5 of 6 shared benchmarks
- you process long inputs — it offers a 1,050,000 token context window
Choose MiMo-V2.5-Pro if…
- cost matters — it's about 20.7x cheaper per token
- you want the most recent training data — it shipped Apr 2026
- you need open weights you can self-host or fine-tune
Performance Benchmarks
Comparative analysis across standard metrics
GPT-5.5 outperforms in 5 benchmarks (Finance Agent v2, GPQA, Humanity's Last Exam, SWE-Bench Pro, Terminal-Bench 2.0), while MiMo-V2.5-Pro is better at 1 benchmark (GDPval-AA).
GPT-5.5 significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.5 ($5.00/1M tokens) is 11.5x more expensive than MiMo-V2.5-Pro ($0.43/1M tokens).
For output processing, GPT-5.5 ($30.00/1M tokens) is 34.5x more expensive than MiMo-V2.5-Pro ($0.87/1M tokens).
In conclusion, GPT-5.5 is more expensive than MiMo-V2.5-Pro.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 accepts 1,050,000 input tokens compared to MiMo-V2.5-Pro's 1,048,576 tokens. MiMo-V2.5-Pro can generate longer responses up to 131,072 tokens, while GPT-5.5 is limited to 128,000 tokens.
Input Capabilities
Supported data types and modalities
GPT-5.5 supports multimodal inputs, whereas MiMo-V2.5-Pro does not.
GPT-5.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.5
MiMo-V2.5-Pro
License
Usage and distribution terms
GPT-5.5 is licensed under a proprietary license, while MiMo-V2.5-Pro uses MIT.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
MIT
Open weights
Release Timeline
When each model was launched
GPT-5.5 was released on 2026-04-23, while MiMo-V2.5-Pro was released on 2026-04-27.
MiMo-V2.5-Pro is 0 month newer than GPT-5.5.
Apr 23, 2026
2 months ago
Apr 27, 2026
2 months ago
4d newerKnowledge Cutoff
When training data ends
GPT-5.5 has a documented knowledge cutoff of 2025-12-01, while MiMo-V2.5-Pro's cutoff date is not specified.
We can confirm GPT-5.5's training data extends to 2025-12-01, but cannot make a direct comparison without MiMo-V2.5-Pro's cutoff date.
Dec 2025
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Provider Availability
GPT-5.5 is available from OpenAI. MiMo-V2.5-Pro is available from Xiaomi, DeepInfra, Novita.
GPT-5.5
MiMo-V2.5-Pro
Outputs Comparison
Key Takeaways
GPT-5.5
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT-5.5 and MiMo-V2.5-Pro side-by-side, then vote on the output you prefer.
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FAQ
Common questions about GPT-5.5 vs MiMo-V2.5-Pro.