Very long inputs
Choose Grok 4.20 Reasoning
Grok 4.20 Reasoning reads up to 1M tokens per request, against 256k for Mistral Medium 3.5.
Grok 4.20 Reasoning vs Mistral Medium 3.5: price, context and capabilities
Choose Grok 4.20 Reasoning for very long inputs. Choose Mistral Medium 3.5 for self-hosting and data control and the latest release.
In short
- A price comparison is not possible: one of them has no comparable published price.
- Grok 4.20 Reasoning reads more per request: 1M tokens against 256k.
- Mistral Medium 3.5 is the newer model (April 2026, against March 2026).
- Only Grok 4.20 Reasoning offers reasoning, prompt caching, batch api.
- Only Mistral Medium 3.5 offers self-hostable.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Self-hosting and data control
Choose Mistral Medium 3.5
Mistral Medium 3.5 has open weights, so you can run it on your own servers; Grok 4.20 Reasoning is only available through its provider.
Latest release
Choose Mistral Medium 3.5
Mistral Medium 3.5 is the newer release (April 2026, against March 2026 for Grok 4.20 Reasoning).
Specifications side by side
| Grok 4.20 Reasoning | Mistral Medium 3.5 | |
|---|---|---|
| Provider | xAI | Mistral AI |
| Category | Language models | Language models |
| Status | Generally available | Generally available |
| Headline price | $1.56 / 1M tokens | No data |
| Input | $1.25 / 1M tokens | No data |
| Output | $2.50 / 1M tokens | No data |
| Cached input | $0.20 / 1M tokens | No data |
| Context window | 1M | 256k |
| Max output | No data | No data |
| Released | March 2026 | April 2026 |
| Knowledge cutoff | No data | No data |
| Licence | Proprietary | Open weights |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Tool calling, Structured output, Self-hostable |
| API model id | grok-4.20-0309-reasoning | mistral-medium-3-5 |
Benchmarks side by side
Leader in bold.
| Benchmark | Grok 4.20 Reasoning | Mistral Medium 3.5 |
|---|---|---|
| Intelligence Index | No data | 14.2 |
| Terminal-Bench Hard | No data | 33.3% |
| SciCode | No data | 40.2% |
| GPQA Diamond | No data | 74.8% |
| Humanity's Last Exam | No data | 13.8% |
| IFBench (instruction following) | No data | 68.8% |
| τ²-Bench (agentic tool use) | No data | 94.2% |
| MMMU-Pro (visual reasoning) | No data | 64.9% |
| Long-context reasoning (AA-LCR) | No data | 69.3% |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose Grok 4.20 Reasoning or Mistral Medium 3.5?
Choose Grok 4.20 Reasoning for very long inputs. Choose Mistral Medium 3.5 for self-hosting and data control and the latest release.
Which is cheaper, Grok 4.20 Reasoning or Mistral Medium 3.5?
A price comparison is not possible: one of them has no comparable published price.
Which has the larger context window, Grok 4.20 Reasoning or Mistral Medium 3.5?
Grok 4.20 Reasoning reads more per request: 1M tokens against 256k.
What is the difference between Grok 4.20 Reasoning and Mistral Medium 3.5?
Grok 4.20 Reasoning is made by xAI and Mistral Medium 3.5 by Mistral AI. A price comparison is not possible: one of them has no comparable published price. Grok 4.20 Reasoning reads more per request: 1M tokens against 256k. Mistral Medium 3.5 is the newer model (April 2026, against March 2026). Only Grok 4.20 Reasoning offers reasoning, prompt caching, batch api. Only Mistral Medium 3.5 offers self-hostable.
Which is newer, Grok 4.20 Reasoning or Mistral Medium 3.5?
Mistral Medium 3.5 was released on April 2026 and Grok 4.20 Reasoning on March 2026.