Agentic
Like-for-like- Grok 4.20
- 26.7
- Supported · #145/152
- Mistral Medium 3.5 128B
- 21.9
- Supported · #150/152
- Basis
- BenchAlign lane · 4 vs 3 public rows
- Reading
- Grok 4.20 leads · intervals overlap
Grok 4.20 vs Mistral Medium 3.5 128B
Updated September 10, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
Grok 4.20 has the higher public score, 67.13 versus 30.13, and the 90% score intervals do not overlap.
6 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
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
Grok 4.20
Grok 4.20 leads on the public agentic lane, 26.7 to 21.9, with Supported evidence for both models, although the 90% intervals overlap.
Confidence: limited
Long documents
Prompts that approach the documented context limit
Grok 4.20
Grok 4.20 has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Grok 4.20
Grok 4.20 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
Mistral Medium 3.5 128B
Mistral Medium 3.5 128B has the lower estimated token cost for this stated workload. Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate. 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
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
17 Grok 4.20 only
6 Shared
1 Mistral Medium 3.5 128B only
- Shared results
- 6
- Grok 4.20 only
- 17
- Mistral Medium 3.5 128B only
- 1
- 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- Grok 4.20
- 49.4
- Supported · #85/183
- Mistral Medium 3.5 128B
- 39.0
- Supported · #140/183
- Basis
- BenchAlign lane · 6 vs 2 public rows
- Reading
- Grok 4.20 leads · intervals overlap
Coding
Directional only- Grok 4.20
- 28.2
- Supported · #141/151
- Mistral Medium 3.5 128B
- 36.9
- Estimated · #127/151
- Basis
- BenchAlign lane · 6 vs 2 public rows
- Reading
- Directional only
Reasoning
Not comparable- Grok 4.20
- 34.2
- 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- Grok 4.20
- Not ranked
- Mistral Medium 3.5 128B
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Grok 4.20
- Not ranked
- Mistral Medium 3.5 128B
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Grok 4.20
- 34.6
- #43/48
- Mistral Medium 3.5 128B
- 55.6
- Unranked · 1 rankable row
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Grok 4.20
- Not ranked
- Mistral Medium 3.5 128B
- 84.0
- #48/123
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Grok 4.20 | Mistral Medium 3.5 128B | Basis | Reading |
|---|---|---|---|---|
| Agentic | 26.7Supported · #145/152 | 21.9Supported · #150/152 | Like-for-likeBenchAlign lane · 4 vs 3 public rows | Grok 4.20 leads · intervals overlap |
| Knowledge | 49.4Supported · #85/183 | 39.0Supported · #140/183 | Like-for-likeBenchAlign lane · 6 vs 2 public rows | Grok 4.20 leads · intervals overlap |
| Coding | 28.2Supported · #141/151 | 36.9Estimated · #127/151 | Directional onlyBenchAlign lane · 6 vs 2 public rows | Directional only |
| Reasoning | 34.2Unranked · 2 rankable rows | 68.6Unranked · 2 rankable rows | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Math | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 34.6#43/48 | 55.6Unranked · 1 rankable row | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | 84.0#48/123 | 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
Grok 4.20: 86.3%Mistral Medium 3.5 128B: 75.3%Normalized gap 11.0Grok 4.20 source Mistral Medium 3.5 128B sourceSWE-bench Verified
Coding
Grok 4.20: 76.7%Mistral Medium 3.5 128B: 77.6%Normalized gap 0.9Grok 4.20 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
- Grok 4.20
- $0.005
- Fits in one request
- Mistral Medium 3.5 128B
- $0.00525
- Fits in one request
Grok 4.20 has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Grok 4.20
- $0.118
- 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
- Grok 4.20
- $0.5
- Fits in one request
- Cached input priced at the published list-input rate
- Mistral Medium 3.5 128B
- $0.405
- Fits in one request
- Cached input priced at the published list-input rate
Mistral Medium 3.5 128B has the lower modeled cost
Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate. 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.
SpecificationGrok 4.20Mistral Medium 3.5 128B
Context window
Maximum documented context; output-token limits may be lower.
Grok 4.20
2M
Mistral Medium 3.5 128B
256K
API model ID
Grok 4.20
Not sourced
Mistral 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.
Grok 4.20
Not published
Mistral Medium 3.5 128B
Not published
Documented inputs
Grok 4.20
Not sourced
Mistral Medium 3.5 128B
Not sourced
Documented outputs
Grok 4.20
Not sourced
Mistral Medium 3.5 128B
Not sourced
Provider availability
Grok 4.20
Not sourced
Mistral Medium 3.5 128B
Not sourced
Reasoning profile
Grok 4.20
Reasoning
Mistral Medium 3.5 128B
Reasoning
Weight access
Grok 4.20
Proprietary
Mistral Medium 3.5 128B
Open Weight
License
Grok 4.20
Proprietary
Mistral Medium 3.5 128B
Open Weight
Release date
Grok 4.20
2026-03-10
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
- Grok 4.20 has the higher public score, 67.13 versus 30.13, and the 90% score intervals do not overlap.
- Workload cost
- Repository review: $0.118 vs $0.0975. Cache-heavy agent loop: $0.5 vs $0.405.
- Context tradeoff
- Grok 4.20 has the larger documented window (2M).
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 evidence24 rows
Agentic
Terminal-Bench 2.0
Grok 4.2047.1%SourceMistral Medium 3.5 128B—Not directly comparable
DeepSearchQA
Grok 4.2062.8%SourceMistral Medium 3.5 128B—Not directly comparable
Gert Labs
Shared sourceGrok 4.2038.36%Mistral Medium 3.5 128B39.10%Mistral Medium 3.5 128B leads this result
Terminal-Bench 2.1 (Vals)
Grok 4.2044.2%SourceMistral Medium 3.5 128B39.0%SourceGrok 4.20 leads this result
τ³-bench results
Grok 4.20—Mistral Medium 3.5 128B91.4%SourceNot directly comparable
Coding
LiveCodeBench Pro
Grok 4.2074.2%SourceMistral Medium 3.5 128B—Not directly comparable
SWE-bench Verified
Grok 4.2076.7%SourceMistral Medium 3.5 128B77.6%SourceMistral Medium 3.5 128B leads this result
SWE-bench Pro
Grok 4.2051.8%SourceMistral Medium 3.5 128B—Not directly comparable
Vibe Code Bench
Grok 4.204.06%SourceMistral Medium 3.5 128B—Not directly comparable
LiveCodeBench (Vals)
Grok 4.2084.3%SourceMistral Medium 3.5 128B—Not directly comparable
SWE-bench (Vals)
Grok 4.2072.2%SourceMistral Medium 3.5 128B66.4%SourceGrok 4.20 leads this result
Reasoning
Knowledge
GPQA-D
Grok 4.2088.5%SourceMistral Medium 3.5 128B—Not directly comparable
HLE w/o tools
Grok 4.2031.6%SourceMistral Medium 3.5 128B—Not directly comparable
HealthBench Hard
Grok 4.2020.3%SourceMistral Medium 3.5 128B—Not directly comparable
MedXpertQA (Text)
Grok 4.2050.2%SourceMistral Medium 3.5 128B—Not directly comparable
GPQA Diamond (Vals)
Grok 4.2088.6%SourceMistral Medium 3.5 128B34.8%SourceGrok 4.20 leads this result
MMLU-Pro (Vals)
Grok 4.2086.3%SourceMistral Medium 3.5 128B75.3%SourceGrok 4.20 leads this result
Multimodal
MMMU-Pro
Grok 4.2075.2%SourceMistral Medium 3.5 128B—Not directly comparable
CharXiv
Grok 4.2060.9%SourceMistral Medium 3.5 128B—Not directly comparable
ERQA
Grok 4.2054.1%SourceMistral Medium 3.5 128B—Not directly comparable
SimpleVQA
Grok 4.2057.4%SourceMistral Medium 3.5 128B—Not directly comparable
MedXpertQA (MM)
Grok 4.2065.8%SourceMistral Medium 3.5 128B—Not directly comparable
Frequently asked questions
Which is better, Grok 4.20 or Mistral Medium 3.5 128B?
Grok 4.20 has the higher public score, 67.13 versus 30.13, 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, Grok 4.20 or Mistral Medium 3.5 128B?
Mistral Medium 3.5 128B scores higher for coding on the public lane, 36.9 to 28.2. 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, Grok 4.20 or Mistral Medium 3.5 128B?
Grok 4.20 leads the public agentic tasks lane, 26.7 to 21.9, with Supported evidence for both models, although the 90% intervals overlap.
Which costs less, Grok 4.20 or Mistral Medium 3.5 128B?
For the stated presets, chat costs $0.005 on Grok 4.20 and $0.00525 on Mistral Medium 3.5 128B; repository review costs $0.118 and $0.0975; the cache-heavy agent loop costs $0.5 and $0.405. Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate. 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, Grok 4.20 or Mistral Medium 3.5 128B?
Grok 4.20 has the larger documented context window: 2M, compared with 256K.
Related comparisons
Last updated September 10, 2026
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