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Devstral Medium vs Grok 4 Fast

Comparing Devstral Medium and Grok 4 Fast across benchmarks, pricing, and capabilities.

Mistral AI · xAI · Updated for 2026

Which is better?

Devstral Medium and Grok 4 Fast trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

On price, Grok 4 Fast is roughly 2.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok 4 Fast also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current benchmark, pricing, and model metadata for 2026.

Choose Devstral Medium

  • you want predictable pricing at $0.40/M input and $2.00/M output

Choose Grok 4 Fast

  • cost matters — it's about 2.9x cheaper per token
  • you process long inputs — it offers a 2,000,000 token context window
  • you want the most recent training data — it shipped Aug 2025

At a glance

The differences that matter most.

Devstral Medium
Mistral AI
Grok 4 Fast
xAI
Benchmark wins
—
—
Input price
$0.40 / M
$0.20 / M
Output price
$2.00 / M
$0.50 / M
Context window
128,000
2,000,000
Released
Jul 2025
Aug 2025
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Devstral Medium and Grok 4 Fastdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Grok 4 Fast costs less

For input processing, Devstral Medium ($0.40/1M tokens) is 2.0x more expensive than Grok 4 Fast ($0.20/1M tokens).

For output processing, Devstral Medium ($2.00/1M tokens) is 4.0x more expensive than Grok 4 Fast ($0.50/1M tokens).

In conclusion, Devstral Medium is more expensive than Grok 4 Fast.*

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

Lowest available price from all providers
Wed Aug 26 2026 • llm-stats.com
Mistral AI
Devstral Medium
Input tokens$0.40
Output tokens$2.00
Best providerMistral
xAI
Grok 4 Fast
Input tokens$0.20
Output tokens$0.50
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Grok 4 Fast accepts 2,000,000 input tokens compared to Devstral Medium's 128,000 tokens. Devstral Medium can generate longer responses up to 128,000 tokens, while Grok 4 Fast is limited to 30,000 tokens.

Mistral AI
Devstral Medium
Input128,000 tokens
Output128,000 tokens
xAI
Grok 4 Fast
Input2,000,000 tokens
Output30,000 tokens
Wed Aug 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Grok 4 Fast supports multimodal inputs, whereas Devstral Medium does not.

Grok 4 Fast can handle both text and other forms of data like images, making it suitable for multimodal applications.

Devstral Medium

Text
Images
Audio
Video

Grok 4 Fast

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Devstral Medium

Proprietary

Closed source

Grok 4 Fast

Proprietary

Closed source

Release Timeline

When each model was launched

Devstral Medium was released on 2025-07-10, while Grok 4 Fast was released on 2025-08-28.

Grok 4 Fast is 2 months newer than Devstral Medium.

Devstral Medium

Jul 10, 2025

1.1 years ago

Grok 4 Fast

Aug 28, 2025

12 months ago

1mo newer

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

Devstral Medium is available from Mistral AI. Grok 4 Fast is available from xAI.

Devstral Medium

mistral logo
Mistral
Input Price:Input: $0.40/1MOutput Price:Output: $2.00/1M

Grok 4 Fast

xai logo
xAI
Input Price:Input: $0.20/1MOutput Price:Output: $0.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Devstral Medium and Grok 4 Fast side-by-side, then vote on the output you prefer.

Devstral Medium
✓ Preferred
Grok 4 Fast
Open in Playground

FAQ

Common questions about Devstral Medium vs Grok 4 Fast.

Which is better, Devstral Medium or Grok 4 Fast?

Devstral Medium (Mistral AI) and Grok 4 Fast (xAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Devstral Medium compare to Grok 4 Fast in benchmarks?

Devstral Medium scores SWE-Bench Verified: 61.6%. Grok 4 Fast scores SimpleQA: 95.0%, HMMT 2025: 93.3%, AIME 2025: 92.0%, GPQA: 85.7%, LiveCodeBench: 80.0%.

Is Devstral Medium cheaper than Grok 4 Fast?

Grok 4 Fast is 2.0x cheaper for input tokens. Devstral Medium costs $0.40/M input and $2.00/M output via mistral. Grok 4 Fast costs $0.20/M input and $0.50/M output via xai.

What are the context window sizes for Devstral Medium and Grok 4 Fast?

Devstral Medium supports 128K tokens and Grok 4 Fast supports 2.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Devstral Medium and Grok 4 Fast?

Key differences include context window (128K vs 2.0M), input pricing ($0.40 vs $0.20/M), multimodal support (no vs yes). See the full comparison above for benchmark-by-benchmark results.

Who makes Devstral Medium and Grok 4 Fast?

Devstral Medium is developed by Mistral AI and Grok 4 Fast is developed by xAI.

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