Gemini 3.1 Pro Preview vs Mistral Medium 3.5.
Verdict by category, tale of the tape, shared benchmarks only, and cost at three workloads — all from the tracked data.
Verdict by category
| Category | Gemini 3.1 Pro Preview | Mistral Medium 3.5 | Winner |
|---|---|---|---|
| League Score | 58.4 | 59.1 | Mistral Medium 3.5 |
| Coding (SWE-bench %) | 75.6 | 77.6 | Mistral Medium 3.5 |
| Reasoning (GPQA %) | 94.3 | — | — |
| Context (tokens) | 1000000 | 256000 | Gemini 3.1 Pro Preview |
| Speed (tok/s) | — | — | — |
| Price (blended $/1M) | $4.50 | $3.00 | Mistral Medium 3.5 (cheaper) |
Tale of the tape
| Spec | Gemini 3.1 Pro Preview | Mistral Medium 3.5 |
|---|---|---|
| Maker | Google DeepMind | Mistral AI |
| Released | Feb 19, 2026 | Apr 28, 2026 |
| League Score | 58 | 59 |
| Context | 1,000,000 tokens | 256,000 tokens |
| Max output | 65,536 | 32,000 |
| $/1M input | $2.00 | $1.50 |
| $/1M output | $12.00 | $7.50 |
| Weights | Closed | Open |
| Speed | — | — |
Head-to-head benchmarks (shared only)
| Benchmark | Gemini 3.1 Pro Preview | Mistral Medium 3.5 |
|---|---|---|
| SWE-bench Verified | 75.6 | 77.6 |
Cost at three workloads
| Workload | Gemini 3.1 Pro Preview | Mistral Medium 3.5 |
|---|---|---|
| Light — 1M in / 250K out | $5.00 | $3.38 |
| Standard — 10M in / 2.5M out | $50.00 | $33.75 |
| Long-context — 50M in / 5M out | $160.00 | $112.50 |
The pick
Pick Gemini 3.1 Pro Preview if you need the bigger context window.
Pick Mistral Medium 3.5 if you want the higher overall League Score; you want the lower running cost; you want downloadable weights / self-hosting; coding is the priority.
All figures from the model database — sources and dates on each model page. Cost your own workload or compare a different pair.
Frequently asked questions
Which is better overall, Gemini 3.1 Pro Preview or Mistral Medium 3.5?
On overall League Score they are effectively tied — Gemini 3.1 Pro Preview scores 58 and Mistral Medium 3.5 scores 59. The category verdicts on this page are where the real differences live.
Which is cheaper, Gemini 3.1 Pro Preview or Mistral Medium 3.5?
Mistral Medium 3.5 is cheaper: $3.00 vs $4.50 blended per 1M tokens (3:1 input/output mix) — about 1.5x less per token.
Which has the bigger context window, Gemini 3.1 Pro Preview or Mistral Medium 3.5?
Gemini 3.1 Pro Preview, with 1M of context against 256K for Mistral Medium 3.5.
Which is better for coding, Gemini 3.1 Pro Preview or Mistral Medium 3.5?
Mistral Medium 3.5 scores higher on SWE-bench Verified, 77.6% vs 75.6% of real GitHub issues resolved.
Are Gemini 3.1 Pro Preview and Mistral Medium 3.5 open source?
Gemini 3.1 Pro Preview is closed weights — API access only; Mistral Medium 3.5 is open weights — it can be downloaded and self-hosted.