Grok Code Fast 1 vs Mistral Medium 3.1

Neither model has an overall benchmark average score in our data, so this comparison is scored test by test across our 12-benchmark suite (1–5 scale).

Where Mistral Medium 3.1 wins outright:

• Strategic analysis: Mistral Medium 3.1 scores 5/5 (tied for 1st among 54 models) vs Grok Code Fast 1's 3/5 (rank 36 of 54). This is a meaningful gap — Mistral Medium 3.1 handles nuanced tradeoff reasoning with real numbers significantly better in our testing.
• Constrained rewriting: Mistral Medium 3.1 scores 5/5 (tied for 1st among 5 models out of 53) vs Grok Code Fast 1's 3/5 (rank 31 of 53). Tasks like compression within hard character limits clearly favor Mistral Medium 3.1.
• Long context: Mistral Medium 3.1 scores 5/5 (tied for 1st among 37 models out of 55) vs Grok Code Fast 1's 4/5 (rank 38 of 55). For retrieval accuracy at 30K+ tokens, Mistral Medium 3.1 has an edge — though Grok Code Fast 1's 256K context window is twice as large as Mistral Medium 3.1's 131K, so raw window size is a separate consideration.
• Persona consistency: Mistral Medium 3.1 scores 5/5 (tied for 1st among 37 models out of 53) vs Grok Code Fast 1's 4/5 (rank 38 of 53). Relevant for chatbots and role-specific assistants.
• Multilingual: Mistral Medium 3.1 scores 5/5 (tied for 1st among 35 models out of 55) vs Grok Code Fast 1's 4/5 (rank 36 of 55). Non-English output quality is better with Mistral Medium 3.1 in our tests.

Where both models tie:

• Agentic planning: Both score 5/5, tied for 1st among 15 models out of 54. Goal decomposition and failure recovery are equally strong — this is Grok Code Fast 1's benchmark peak.
• Tool calling: Both score 4/5, rank 18 of 54 (29 models share this score). Function selection and argument accuracy are equivalent.
• Structured output: Both score 4/5, rank 26 of 54 (27 models share this score). JSON schema compliance is on par.
• Classification: Both score 4/5, tied for 1st among 30 models out of 53. Routing and categorization are equivalent.
• Faithfulness: Both score 4/5, rank 34 of 55 (18 models share this score). Source adherence is identical.
• Safety calibration: Both score 2/5, rank 12 of 55 (20 models share this score). Neither excels here — both sit at the 50th percentile of our test set on this dimension.
• Creative problem solving: Both score 3/5, rank 30 of 54 (17 models share this score). Below-median performance for both on non-obvious ideation.

Where Grok Code Fast 1 wins: None. In our testing, Grok Code Fast 1 does not outscore Mistral Medium 3.1 on any of the 12 benchmarks.

One hardware note: Grok Code Fast 1 supports reasoning tokens (its quirks flag uses_reasoning_tokens: true) and exposes reasoning traces, which can help developers debug and steer agentic coding workflows — a practical advantage not captured in aggregate benchmark scores. Mistral Medium 3.1 also adds image input support (text+image->text modality) that Grok Code Fast 1 lacks (text->text only), which is relevant for multimodal tasks.

Grok Code Fast 1 costs $0.20 per MTok input and $1.50 per MTok output. Mistral Medium 3.1 costs $0.40 per MTok input and $2.00 per MTok output — double the input price and 33% more on output. In practice: at 1M output tokens/month, that's $1.50 vs $2.00 — a $0.50 difference, negligible for most teams. At 10M output tokens, the gap widens to $5,000 vs $20,000 — wait, let's be precise: $15,000 vs $20,000, a $5,000 monthly delta. At 100M output tokens, you're looking at $150,000 vs $200,000 — a $50,000/month difference that matters for high-throughput production pipelines. The cost gap is most relevant to developers running continuous automated pipelines (code review bots, document processors, bulk classification) rather than interactive users. For the benchmarks where both models tie — agentic planning, tool calling, structured output, classification — Grok Code Fast 1 is the rational cost choice. For workloads that require strong multilingual, long-context, or strategic analysis performance, Mistral Medium 3.1's benchmark wins may be worth the premium.

Choose Grok Code Fast 1 if: Your primary workload is agentic coding pipelines where you need reasoning traces for debugging and steering, you're running at high output volume (100M+ tokens/month) where the $50,000/month cost gap is material, or you need a context window larger than 131K tokens (Grok Code Fast 1 supports 256K vs Mistral Medium 3.1's 131K). Given their identical scores on agentic planning and tool calling, Grok Code Fast 1 delivers the same performance on those dimensions for less money.

Choose Mistral Medium 3.1 if: You need reliable multilingual output, handle long documents requiring high retrieval accuracy, do strategic analysis or business reasoning tasks, need to maintain personas in chatbot or assistant products, or work with constrained editorial rewriting. Mistral Medium 3.1 also handles image inputs, making it the only option here for multimodal workflows. For most enterprise general-purpose use cases — documents, analysis, content — Mistral Medium 3.1's benchmark lead across five dimensions is worth the price premium unless volume is very high.