Model Comparison

Mistral Medium 3.5 vs U2Which is better in 2026?

Comparing Mistral Medium 3.5 and U2 across benchmarks, pricing, and capabilities.

Verdict: Mistral Medium 3.5 vs U2 — which is better?

Mistral Medium 3.5 (by Mistral AI) and U2 (by Unisound) 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.

On price, U2 is roughly 16.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Mistral Medium 3.5 if…

  • you need open weights you can self-host or fine-tune

Choose U2 if…

  • cost matters — it's about 16.0x cheaper per token
  • you want the most recent training data — it shipped Jun 2026

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Mistral Medium 3.5 and U2don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

U2 costs less

For input processing, Mistral Medium 3.5 ($1.50/1M tokens) is 10.0x more expensive than U2 ($0.15/1M tokens).

For output processing, Mistral Medium 3.5 ($7.50/1M tokens) is 25.0x more expensive than U2 ($0.30/1M tokens).

In conclusion, Mistral Medium 3.5 is more expensive than U2.*

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

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Mistral AI
Mistral Medium 3.5
Input tokens$1.50
Output tokens$7.50
Best providerMistral
Unisound
U2
Input tokens$0.15
Output tokens$0.30
Best providerUnisound
Notice missing or incorrect data?Start an Issue→

Model Size

Parameter count comparison

138.0B diff

U2 has 138.0B more parameters than Mistral Medium 3.5, making it 107.8% larger.

Mistral AI
Mistral Medium 3.5
128.0Bparameters
Unisound
U2
266.0Bparameters
128.0B
Mistral Medium 3.5
266.0B
U2

Context Window

Maximum input and output token capacity

Only Mistral Medium 3.5 specifies input context (256,000 tokens). Only Mistral Medium 3.5 specifies output context (256,000 tokens).

Mistral AI
Mistral Medium 3.5
Input256,000 tokens
Output256,000 tokens
Unisound
U2
Input- tokens
Output- tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Mistral Medium 3.5 supports multimodal inputs, whereas U2 does not.

Mistral Medium 3.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Mistral Medium 3.5

Text
Images
Audio
Video

U2

Text
Images
Audio
Video

License

Usage and distribution terms

Mistral Medium 3.5 is licensed under Modified MIT License, while U2 uses a proprietary license.

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

Mistral Medium 3.5

Modified MIT License

Open weights

U2

Proprietary

Closed source

Release Timeline

When each model was launched

Mistral Medium 3.5 was released on 2026-04-29, while U2 was released on 2026-06-05.

U2 is 1 month newer than Mistral Medium 3.5.

Mistral Medium 3.5

Apr 29, 2026

2 months ago

U2

Jun 5, 2026

1 months ago

1mo newer

Knowledge Cutoff

When training data ends

U2 has a documented knowledge cutoff of 2026-01-31, while Mistral Medium 3.5's cutoff date is not specified.

We can confirm U2's training data extends to 2026-01-31, but cannot make a direct comparison without Mistral Medium 3.5's cutoff date.

Mistral Medium 3.5

—

U2

Jan 2026

Provider Availability

Mistral Medium 3.5 is available from Mistral AI. U2 is available from Unisound.

Mistral Medium 3.5

mistral logo
Mistral
Input Price:Input: $1.50/1MOutput Price:Output: $7.50/1M

U2

unisound logo
Unisound
Input Price:Input: $0.15/1MOutput Price:Output: $0.30/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Mistral AI
Larger context window (256,000 tokens)
Supports multimodal inputs
Has open weights
Unisound
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Mistral Medium 3.5 and U2 side-by-side, then vote on the output you prefer.

Mistral Medium 3.5
✓ Preferred
U2
Open in Playground
AI Model Comparison Table
Feature
Mistral AI
Mistral Medium 3.5
Unisound
U2

FAQ

Common questions about Mistral Medium 3.5 vs U2.

Which is better, Mistral Medium 3.5 or U2?

Mistral Medium 3.5 (Mistral AI) and U2 (Unisound) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Mistral Medium 3.5 compare to U2 in benchmarks?

Mistral Medium 3.5 scores COLLIE: 95.8%, Tau3 Telecom: 91.4%, AIME 2025: 86.3%, SWE-Bench Verified: 77.6%, Tau3 Retail: 76.1%.

Is Mistral Medium 3.5 cheaper than U2?

U2 is 10.0x cheaper for input tokens. Mistral Medium 3.5 costs $1.50/M input and $7.50/M output via mistral. U2 costs $0.15/M input and $0.30/M output via unisound.

What are the context window sizes for Mistral Medium 3.5 and U2?

Mistral Medium 3.5 supports 256K tokens and U2 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Mistral Medium 3.5 and U2?

Key differences include input pricing ($1.50 vs $0.15/M), multimodal support (yes vs no), licensing (Modified MIT License vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Mistral Medium 3.5 and U2?

Mistral Medium 3.5 is developed by Mistral AI and U2 is developed by Unisound.

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