Agentic
Like-for-like- Gemini 3.1 Pro
- 39.7
- Supported · #121/154
- Mistral Medium 3.5 128B
- 21.9
- Supported · #152/154
- Basis
- BenchAlign lane · 6 vs 3 public rows
- Reading
- Gemini 3.1 Pro leads
Gemini 3.1 Pro vs Mistral Medium 3.5 128B
Decision reading
Gemini 3.1 Pro has the higher public score, 70.14 versus 42.56, and the 90% score intervals do not overlap.
5 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
Updated September 18, 2026. Rank says Gemini 3.1 Pro is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.
Both of these models will change. Get the price, version and retirement notices for the pair, each with its source. Follow model changes
Share or export
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Agentic work
Tool use, computer use, and multi-step task completion
Gemini 3.1 Pro
Gemini 3.1 Pro leads on the public agentic lane, 39.7 to 21.9, with Supported evidence for both models and non-overlapping 90% intervals.
Confidence: stronger
Long documents
Prompts that approach the documented context limit
Gemini 3.1 Pro
Gemini 3.1 Pro has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Mistral Medium 3.5 128B
Mistral Medium 3.5 128B has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Show secondary and unsupported calls
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Gemini 3.1 Pro
Gemini 3.1 Pro has the lower estimated token cost for this stated workload. Mistral Medium 3.5 128B has no published cached-input rate, so cached tokens use its listed input rate.
Confidence: rate-fallback
Repository review cost
50K fresh input + 3K output tokens
Mistral Medium 3.5 128B
Mistral Medium 3.5 128B has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
Mistral Medium 3.5 128B is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.
Confidence: limited
Which one for a specific job
Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.
The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.
46.1Gemini 3.1 Pro39.2Mistral Medium 3.5 128B
Directional only · BenchAlign
Gemini 3.1 Pro scores higher, but at least one score rests on Estimated evidence or a different benchmark set. Directional only, no winner.
Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
23 Gemini 3.1 Pro only
5 Shared
2 Mistral Medium 3.5 128B only
- Shared results
- 5
- Gemini 3.1 Pro only
- 23
- Mistral Medium 3.5 128B only
- 2
- Like-for-like categories
- 2 / 8
1 category rests on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
Knowledge
Like-for-like- Gemini 3.1 Pro
- 66.0
- Supported · #22/184
- Mistral Medium 3.5 128B
- 40.6
- Supported · #133/184
- Basis
- BenchAlign lane · 6 vs 2 public rows
- Reading
- Gemini 3.1 Pro leads · intervals overlap
Coding
Directional only- Gemini 3.1 Pro
- 46.1
- Supported · #88/154
- Mistral Medium 3.5 128B
- 39.2
- Estimated · #124/154
- Basis
- BenchAlign lane · 5 vs 2 public rows
- Reading
- Directional only
Reasoning
Not comparable- Gemini 3.1 Pro
- 50.7
- Unranked · 2 rankable rows
- Mistral Medium 3.5 128B
- 68.6
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- Gemini 3.1 Pro
- 54.2
- Unranked · 2 rankable rows
- Mistral Medium 3.5 128B
- Not ranked
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Gemini 3.1 Pro
- Not ranked
- Mistral Medium 3.5 128B
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Gemini 3.1 Pro
- 79.1
- #12/48
- Mistral Medium 3.5 128B
- 55.7
- Unranked · 1 rankable row
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Gemini 3.1 Pro
- Not ranked
- Mistral Medium 3.5 128B
- 82.6
- #48/124
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Gemini 3.1 Pro | Mistral Medium 3.5 128B | Basis | Reading |
|---|---|---|---|---|
| Agentic | 39.7Supported · #121/154 | 21.9Supported · #152/154 | Like-for-likeBenchAlign lane · 6 vs 3 public rows | Gemini 3.1 Pro leads |
| Knowledge | 66.0Supported · #22/184 | 40.6Supported · #133/184 | Like-for-likeBenchAlign lane · 6 vs 2 public rows | Gemini 3.1 Pro leads · intervals overlap |
| Coding | 46.1Supported · #88/154 | 39.2Estimated · #124/154 | Directional onlyBenchAlign lane · 5 vs 2 public rows | Directional only |
| Reasoning | 50.7Unranked · 2 rankable rows | 68.6Unranked · 2 rankable rows | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Math | 54.2Unranked · 2 rankable rows | Not ranked | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 79.1#12/48 | 55.7Unranked · 1 rankable row | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | 82.6#48/124 | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign) differ from the provisional-lane categories. Unranked scores sit on the lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
MMLU-Pro (Vals)
Knowledge
Gemini 3.1 Pro: 91.0%Mistral Medium 3.5 128B: 75.3%Normalized gap 15.7Gemini 3.1 Pro source Mistral Medium 3.5 128B source
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Gemini 3.1 Pro
- $0.008
- Fits in one request
- Mistral Medium 3.5 128B
- $0.00525
- Fits in one request
Mistral Medium 3.5 128B has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Gemini 3.1 Pro
- $0.136
- Fits in one request
- Mistral Medium 3.5 128B
- $0.0975
- Fits in one request
Mistral Medium 3.5 128B has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Gemini 3.1 Pro
- $0.2
- Fits in one request
- Mistral Medium 3.5 128B
- $0.405
- Fits in one request
- Cached input priced at the published list-input rate
Gemini 3.1 Pro has the lower modeled cost
Mistral Medium 3.5 128B has no published cached-input rate, so cached tokens use its listed input rate.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationGemini 3.1 ProMistral Medium 3.5 128B
Context window
Maximum documented context; output-token limits may be lower.
Gemini 3.1 Pro
Mistral Medium 3.5 128B
256K
API model ID
Gemini 3.1 Pro
gemini-3.1-pro-preview
Google Gemini 3.1 Pro Preview model documentationMistral Medium 3.5 128B
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Gemini 3.1 Pro
$0.2 per 1M cached input tokens
Google Gemini API pricingMistral Medium 3.5 128B
Not published
Documented inputs
Gemini 3.1 Pro
text, image, video, audio, pdf
Google Gemini 3.1 Pro Preview model documentationMistral Medium 3.5 128B
Not sourced
Documented outputs
Gemini 3.1 Pro
Mistral Medium 3.5 128B
Not sourced
Provider availability
Gemini 3.1 Pro
Preview · Gemini API, Google AI Studio
Google Gemini model catalogMistral Medium 3.5 128B
Not sourced
Reasoning profile
Gemini 3.1 Pro
Reasoning
Mistral Medium 3.5 128B
Reasoning
Weight access
Gemini 3.1 Pro
Proprietary
Mistral Medium 3.5 128B
Open Weight
License
Gemini 3.1 Pro
Proprietary
Mistral Medium 3.5 128B
Open Weight
Release date
Gemini 3.1 Pro
2026-02-19
Mistral Medium 3.5 128B
2026-04-29
If you already use one of these models
- Deployment change
- The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
- Quality signal
- Gemini 3.1 Pro has the higher public score, 70.14 versus 42.56, and the 90% score intervals do not overlap.
- Workload cost
- Repository review: $0.136 vs $0.0975. Cache-heavy agent loop: $0.2 vs $0.405.
- Context tradeoff
- Gemini 3.1 Pro has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence30 rows
Agentic
Claw-Eval
Gemini 3.1 Pro57.8%SourceMistral Medium 3.5 128B—Not directly comparable
DeepSearchQA
Gemini 3.1 Pro69.7%SourceMistral Medium 3.5 128B—Not directly comparable
τ²-bench results
Gemini 3.1 Pro95.6%SourceMistral Medium 3.5 128B—Not directly comparable
Gert Labs
Shared sourceGemini 3.1 Pro56.87%Mistral Medium 3.5 128B39.10%Gemini 3.1 Pro leads this result
ResearchClawBench
Gemini 3.1 Pro13.3%SourceMistral Medium 3.5 128B—Not directly comparable
Terminal-Bench 2.1 (Vals)
Gemini 3.1 Pro70.8%SourceMistral Medium 3.5 128B39.0%SourceGemini 3.1 Pro leads this result
τ³-bench results
Gemini 3.1 Pro—Mistral Medium 3.5 128B91.4%SourceNot directly comparable
Coding
LiveCodeBench Pro
Gemini 3.1 Pro82.9%SourceMistral Medium 3.5 128B—Not directly comparable
React Native Evals
Gemini 3.1 Pro78.9%SourceMistral Medium 3.5 128B—Not directly comparable
Vibe Code Bench
Gemini 3.1 Pro32.03%SourceMistral Medium 3.5 128B—Not directly comparable
LiveCodeBench (Vals)
Gemini 3.1 Pro88.5%SourceMistral Medium 3.5 128B—Not directly comparable
SWE-bench (Vals)
Gemini 3.1 Pro78.8%SourceMistral Medium 3.5 128B66.4%SourceGemini 3.1 Pro leads this result
SWE-bench Verified
Gemini 3.1 Pro—Mistral Medium 3.5 128B77.6%SourceNot directly comparable
Reasoning
Knowledge
GPQA-D
Gemini 3.1 Pro94.3%SourceMistral Medium 3.5 128B—Not directly comparable
HLE w/o tools
Gemini 3.1 Pro45.4%SourceMistral Medium 3.5 128B—Not directly comparable
HealthBench Hard
Gemini 3.1 Pro20.6%SourceMistral Medium 3.5 128B—Not directly comparable
MedXpertQA (Text)
Gemini 3.1 Pro71.5%SourceMistral Medium 3.5 128B—Not directly comparable
GPQA Diamond (Vals)
Gemini 3.1 Pro95.5%SourceMistral Medium 3.5 128B34.8%SourceGemini 3.1 Pro leads this result
MMLU-Pro (Vals)
Gemini 3.1 Pro91.0%SourceMistral Medium 3.5 128B75.3%SourceGemini 3.1 Pro leads this result
Math
Multimodal
MMMU-Pro
Gemini 3.1 Pro83.9%SourceMistral Medium 3.5 128B—Not directly comparable
CharXiv
Gemini 3.1 Pro80.2%SourceMistral Medium 3.5 128B—Not directly comparable
ERQA
Gemini 3.1 Pro69.4%SourceMistral Medium 3.5 128B—Not directly comparable
SimpleVQA
Gemini 3.1 Pro72.4%SourceMistral Medium 3.5 128B—Not directly comparable
ScreenSpot Pro
Gemini 3.1 Pro84.4%SourceMistral Medium 3.5 128B—Not directly comparable
ZeroBench
Gemini 3.1 Pro29.0%SourceMistral Medium 3.5 128B—Not directly comparable
MedXpertQA (MM)
Gemini 3.1 Pro81.3%SourceMistral Medium 3.5 128B—Not directly comparable
Questions
Which is better, Gemini 3.1 Pro or Mistral Medium 3.5 128B?
Gemini 3.1 Pro has the higher public score, 70.14 versus 42.56, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.
Which is better for coding, Gemini 3.1 Pro or Mistral Medium 3.5 128B?
Gemini 3.1 Pro scores higher for coding on the public lane, 46.1 to 39.2. Mistral Medium 3.5 128B is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.
Which is better for agentic tasks, Gemini 3.1 Pro or Mistral Medium 3.5 128B?
Gemini 3.1 Pro leads the public agentic tasks lane, 39.7 to 21.9, with Supported evidence for both models and non-overlapping 90% intervals.
Which costs less, Gemini 3.1 Pro or Mistral Medium 3.5 128B?
For the stated presets, chat costs $0.008 on Gemini 3.1 Pro and $0.00525 on Mistral Medium 3.5 128B; repository review costs $0.136 and $0.0975; the cache-heavy agent loop costs $0.2 and $0.405. Mistral Medium 3.5 128B has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, Gemini 3.1 Pro or Mistral Medium 3.5 128B?
Gemini 3.1 Pro has the larger documented context window: 1M, compared with 256K.
Related comparisons
Last updated September 18, 2026
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