Agentic
Directional only- GPT-5.5 Pro
- 60.6
- Estimated · #24/151
- Mistral Small 4
- 41.3
- Estimated · #116/151
- Basis
- BenchAlign lane · 1 vs 0 public rows
- Reading
- Directional only
GPT-5.5 Pro vs Mistral Small 4
Updated September 4, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. Use the documented cost, context, and runtime rows instead.
0 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-5.5 Pro
GPT-5.5 Pro has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Mistral Small 4
Mistral Small 4 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
Mistral Small 4
Mistral Small 4 has the lower estimated token cost for this stated workload. GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate. Mistral Small 4 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
Mistral Small 4
Mistral Small 4 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
GPT-5.5 Pro is not ranked on the public lane for coding, so no winner is named for coding.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
GPT-5.5 Pro and Mistral Small 4 are 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.
6 GPT-5.5 Pro only
- Shared results
- 0
- GPT-5.5 Pro only
- 6
- Mistral Small 4 only
- 0
- Like-for-like categories
- 0 / 8
2 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.
Knowledge
Directional only- GPT-5.5 Pro
- 61.1
- Estimated · #36/181
- Mistral Small 4
- 43.0
- Estimated · #125/181
- Basis
- BenchAlign lane · 2 vs 0 public rows
- Reading
- Directional only
Coding
Not comparable- GPT-5.5 Pro
- Not ranked
- Mistral Small 4
- 43.8
- Estimated · #120/183
- Basis
- BenchAlign lane · 0 vs 0 public rows
- Reading
- Not comparable
Reasoning
Not comparable- GPT-5.5 Pro
- Not ranked
- Mistral Small 4
- 55.0
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- GPT-5.5 Pro
- 70.2
- Unranked · 3 rankable rows
- Mistral Small 4
- Not ranked
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- GPT-5.5 Pro
- Not ranked
- Mistral Small 4
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- GPT-5.5 Pro
- Not ranked
- Mistral Small 4
- 43.7
- Unranked · 1 rankable row
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- GPT-5.5 Pro
- Not ranked
- Mistral Small 4
- 57.0
- #73/120
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | GPT-5.5 Pro | Mistral Small 4 | Basis | Reading |
|---|---|---|---|---|
| Agentic | 60.6Estimated · #24/151 | 41.3Estimated · #116/151 | Directional onlyBenchAlign lane · 1 vs 0 public rows | Directional only |
| Knowledge | 61.1Estimated · #36/181 | 43.0Estimated · #125/181 | Directional onlyBenchAlign lane · 2 vs 0 public rows | Directional only |
| Coding | Not ranked | 43.8Estimated · #120/183 | Not comparableBenchAlign lane · 0 vs 0 public rows | Not comparable |
| Reasoning | Not ranked | 55.0Unranked · 2 rankable rows | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | 70.2Unranked · 3 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 | Not ranked | 43.7Unranked · 1 rankable row | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | 57.0#73/120 | 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.
A shared-evidence shape is not available.
BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.
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-5.5 Pro
- $0.12
- Fits in one request
- Mistral Small 4
- $0.00045
- Fits in one request
Mistral Small 4 has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- GPT-5.5 Pro
- $2.04
- Fits in one request
- Mistral Small 4
- $0.0093
- Fits in one request
Mistral Small 4 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-5.5 Pro
- $8.40
- Fits in one request
- Cached input priced at the published list-input rate
- Mistral Small 4
- $0.039
- Fits in one request
- Cached input priced at the published list-input rate
Mistral Small 4 has the lower modeled cost
GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate. Mistral Small 4 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-5.5 ProMistral Small 4
Context window
Maximum documented context; output-token limits may be lower.
GPT-5.5 Pro
Mistral Small 4
256K
API model ID
GPT-5.5 Pro
gpt-5.5-pro
OpenAI GPT-5.5 Pro model documentationMistral Small 4
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
GPT-5.5 Pro
Not published
OpenAI pricingMistral Small 4
Not published
Documented inputs
GPT-5.5 Pro
text, image
OpenAI model catalogMistral Small 4
Not sourced
Documented outputs
GPT-5.5 Pro
Mistral Small 4
Not sourced
Provider availability
GPT-5.5 Pro
Generally Available · OpenAI Responses API
OpenAI model catalogMistral Small 4
Not sourced
Reasoning profile
GPT-5.5 Pro
Reasoning
Mistral Small 4
Non-Reasoning
Weight access
GPT-5.5 Pro
Proprietary
Mistral Small 4
Open Weight
License
GPT-5.5 Pro
Proprietary
Mistral Small 4
Open Weight
Release date
GPT-5.5 Pro
2026-04-23
Mistral Small 4
2026-02-20
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
- The public evidence has no benchmark result shared by both models, so it does not support a quality verdict.
- Workload cost
- Repository review: $2.04 vs $0.0093. Cache-heavy agent loop: $8.40 vs $0.039.
- Context tradeoff
- GPT-5.5 Pro has the larger documented window (1.05M).
Run the same representative tasks against both endpoints before changing production traffic.
Self-host vs API cost
Estimates at 50,000 req/day · 1000 tokens/req average.
GPT-5.5 Pro
API / mo$157,500
Self-host / moNot listed
Break-even—
Proprietary model — self-hosting not applicable.
Mistral Small 4
API / mo$563
Self-host / mo$2,278
Break-even266M/day
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence6 rows
Frequently asked questions
Which is better, GPT-5.5 Pro or Mistral Small 4?
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. The page therefore keeps the decision tied to the specific documented workload.
Which is better for coding, GPT-5.5 Pro or Mistral Small 4?
GPT-5.5 Pro is not ranked on the public lane for coding, so no winner is named for coding.
Which is better for agentic tasks, GPT-5.5 Pro or Mistral Small 4?
GPT-5.5 Pro scores higher for agentic tasks on the public lane, 60.6 to 41.3. GPT-5.5 Pro and Mistral Small 4 are 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-5.5 Pro or Mistral Small 4?
For the stated presets, chat costs $0.12 on GPT-5.5 Pro and $0.00045 on Mistral Small 4; repository review costs $2.04 and $0.0093; the cache-heavy agent loop costs $8.40 and $0.039. GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate. Mistral Small 4 has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, GPT-5.5 Pro or Mistral Small 4?
GPT-5.5 Pro has the larger documented context window: 1.05M, compared with 256K.
Related comparisons
Last updated September 4, 2026
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