Knowledge
Like-for-like- GPT-5.4 mini
- 55.6
- Supported · #52/183
- Mistral Medium 3.5 128B
- 39.0
- Supported · #140/183
- Basis
- BenchAlign lane · 5 vs 2 public rows
- Reading
- GPT-5.4 mini leads · intervals overlap
GPT-5.4 mini 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
GPT-5.4 mini has the higher public score, 61.11 versus 30.13, and the 90% score intervals do not overlap.
4 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.
Long documents
Prompts that approach the documented context limit
GPT-5.4 mini
GPT-5.4 mini has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
GPT-5.4 mini
GPT-5.4 mini has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
GPT-5.4 mini
GPT-5.4 mini 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
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
GPT-5.4 mini
GPT-5.4 mini 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
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
GPT-5.4 mini is scored on Estimated evidence for agentic, 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.
15 GPT-5.4 mini only
4 Shared
3 Mistral Medium 3.5 128B only
- Shared results
- 4
- GPT-5.4 mini only
- 15
- Mistral Medium 3.5 128B only
- 3
- Like-for-like categories
- 1 / 8
3 categories rest 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.
Agentic
Directional only- GPT-5.4 mini
- 39.1
- Estimated · #119/152
- Mistral Medium 3.5 128B
- 21.9
- Supported · #150/152
- Basis
- BenchAlign lane · 6 vs 3 public rows
- Reading
- Directional only
Coding
Directional only- GPT-5.4 mini
- 42.7
- Supported · #104/151
- Mistral Medium 3.5 128B
- 36.9
- Estimated · #127/151
- Basis
- BenchAlign lane · 4 vs 2 public rows
- Reading
- Directional only
Instruction following
Directional only- GPT-5.4 mini
- 89.8
- #23/123
- Mistral Medium 3.5 128B
- 84.0
- #48/123
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Directional only
Reasoning
Not comparable- GPT-5.4 mini
- 73.9
- Unranked · 2 rankable rows
- Mistral Medium 3.5 128B
- 68.6
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- GPT-5.4 mini
- 44.5
- 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- GPT-5.4 mini
- Not ranked
- Mistral Medium 3.5 128B
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- GPT-5.4 mini
- 57.2
- #31/48
- Mistral Medium 3.5 128B
- 55.6
- Unranked · 1 rankable row
- Basis
- Provisional lane · 1 vs 0 weighted rows
- Reading
- Not comparable
| Category | GPT-5.4 mini | Mistral Medium 3.5 128B | Basis | Reading |
|---|---|---|---|---|
| Knowledge | 55.6Supported · #52/183 | 39.0Supported · #140/183 | Like-for-likeBenchAlign lane · 5 vs 2 public rows | GPT-5.4 mini leads · intervals overlap |
| Agentic | 39.1Estimated · #119/152 | 21.9Supported · #150/152 | Directional onlyBenchAlign lane · 6 vs 3 public rows | Directional only |
| Coding | 42.7Supported · #104/151 | 36.9Estimated · #127/151 | Directional onlyBenchAlign lane · 4 vs 2 public rows | Directional only |
| Instruction following | 89.8#23/123 | 84.0#48/123 | Directional onlyProvisional lane · 0 vs 0 weighted rows | Directional only |
| Reasoning | 73.9Unranked · 2 rankable rows | 68.6Unranked · 2 rankable rows | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | 44.5Unranked · 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 | 57.2#31/48 | 55.6Unranked · 1 rankable row | Not comparableProvisional lane · 1 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
GPT-5.4 mini: 84.6%Mistral Medium 3.5 128B: 75.3%Normalized gap 9.3GPT-5.4 mini 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
- GPT-5.4 mini
- $0.003
- Fits in one request
- Mistral Medium 3.5 128B
- $0.00525
- Fits in one request
GPT-5.4 mini has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- GPT-5.4 mini
- $0.051
- Fits in one request
- Mistral Medium 3.5 128B
- $0.0975
- Fits in one request
GPT-5.4 mini has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- GPT-5.4 mini
- $0.075
- Fits in one request
- Mistral Medium 3.5 128B
- $0.405
- Fits in one request
- Cached input priced at the published list-input rate
GPT-5.4 mini 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.
SpecificationGPT-5.4 miniMistral Medium 3.5 128B
Context window
Maximum documented context; output-token limits may be lower.
GPT-5.4 mini
Mistral Medium 3.5 128B
256K
API model ID
GPT-5.4 mini
gpt-5.4-mini
OpenAI GPT-5.4 mini 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.
GPT-5.4 mini
$0.075 per 1M cached input tokens
OpenAI pricingMistral Medium 3.5 128B
Not published
Documented inputs
GPT-5.4 mini
text, image
OpenAI model catalogMistral Medium 3.5 128B
Not sourced
Documented outputs
GPT-5.4 mini
Mistral Medium 3.5 128B
Not sourced
Provider availability
GPT-5.4 mini
Generally Available · OpenAI Responses API
OpenAI model catalogMistral Medium 3.5 128B
Not sourced
Reasoning profile
GPT-5.4 mini
Reasoning
Mistral Medium 3.5 128B
Reasoning
Weight access
GPT-5.4 mini
Proprietary
Mistral Medium 3.5 128B
Open Weight
License
GPT-5.4 mini
Proprietary
Mistral Medium 3.5 128B
Open Weight
Release date
GPT-5.4 mini
2026-03-17
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
- GPT-5.4 mini has the higher public score, 61.11 versus 30.13, and the 90% score intervals do not overlap.
- Workload cost
- Repository review: $0.051 vs $0.0975. Cache-heavy agent loop: $0.075 vs $0.405.
- Context tradeoff
- GPT-5.4 mini has the larger documented window (400K).
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 evidence22 rows
Agentic
Terminal-Bench 2.0
GPT-5.4 mini60%SourceMistral Medium 3.5 128B—Not directly comparable
OSWorld-Verified
GPT-5.4 mini72.1%SourceMistral Medium 3.5 128B—Not directly comparable
MCP Atlas
GPT-5.4 mini57.7%SourceMistral Medium 3.5 128B—Not directly comparable
Toolathlon
GPT-5.4 mini42.9%SourceMistral Medium 3.5 128B—Not directly comparable
τ²-bench results
GPT-5.4 mini93.4%SourceMistral Medium 3.5 128B—Not directly comparable
Terminal-Bench 2.1 (Vals)
GPT-5.4 mini54.7%SourceMistral Medium 3.5 128B39.0%SourceGPT-5.4 mini leads this result
τ³-bench results
GPT-5.4 mini—Mistral Medium 3.5 128B91.4%SourceNot directly comparable
Gert Labs
GPT-5.4 mini—Mistral Medium 3.5 128B39.10%SourceNot directly comparable
Coding
Vibe Code Bench
GPT-5.4 mini47.97%SourceMistral Medium 3.5 128B—Not directly comparable
FrontierCode 1.1 Main
GPT-5.4 mini27.0%SourceMistral Medium 3.5 128B—Not directly comparable
LiveCodeBench (Vals)
GPT-5.4 mini81.5%SourceMistral Medium 3.5 128B—Not directly comparable
SWE-bench (Vals)
GPT-5.4 mini73.0%SourceMistral Medium 3.5 128B66.4%SourceGPT-5.4 mini leads this result
SWE-bench Verified
GPT-5.4 mini—Mistral Medium 3.5 128B77.6%SourceNot directly comparable
Knowledge
GPQA
GPT-5.4 mini88%SourceMistral Medium 3.5 128B—Not directly comparable
HLE
GPT-5.4 mini41.5%SourceMistral Medium 3.5 128B—Not directly comparable
HLE w/o tools
GPT-5.4 mini28.2%SourceMistral Medium 3.5 128B—Not directly comparable
GPQA Diamond (Vals)
GPT-5.4 mini83.1%SourceMistral Medium 3.5 128B34.8%SourceGPT-5.4 mini leads this result
MMLU-Pro (Vals)
GPT-5.4 mini84.6%SourceMistral Medium 3.5 128B75.3%SourceGPT-5.4 mini leads this result
Math
Multimodal
Frequently asked questions
Which is better, GPT-5.4 mini or Mistral Medium 3.5 128B?
GPT-5.4 mini has the higher public score, 61.11 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, GPT-5.4 mini or Mistral Medium 3.5 128B?
GPT-5.4 mini scores higher for coding on the public lane, 42.7 to 36.9. 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, GPT-5.4 mini or Mistral Medium 3.5 128B?
GPT-5.4 mini scores higher for agentic tasks on the public lane, 39.1 to 21.9. GPT-5.4 mini is scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.
Which costs less, GPT-5.4 mini or Mistral Medium 3.5 128B?
For the stated presets, chat costs $0.003 on GPT-5.4 mini and $0.00525 on Mistral Medium 3.5 128B; repository review costs $0.051 and $0.0975; the cache-heavy agent loop costs $0.075 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, GPT-5.4 mini or Mistral Medium 3.5 128B?
GPT-5.4 mini has the larger documented context window: 400K, compared with 256K.
Related comparisons
Last updated September 10, 2026
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