Agentic
Directional only- Gemma 4 31B
- 27.6
- Supported · #140/151
- GPT-5.5 Pro
- 60.6
- Estimated · #24/151
- Basis
- BenchAlign lane · 1 vs 1 public rows
- Reading
- Directional only
Gemma 4 31B vs GPT-5.5 Pro
Updated September 4, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
GPT-5.5 Pro has the higher public score estimate, 63.07 versus 58.69, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
2 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
Show secondary and unsupported calls
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 is scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.
Confidence: limited
Chat turn cost
1K fresh input + 500 output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: rate-fallback
Repository review cost
50K fresh input + 3K output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
6 Gemma 4 31B only
2 Shared
4 GPT-5.5 Pro only
- Shared results
- 2
- Gemma 4 31B only
- 6
- GPT-5.5 Pro only
- 4
- 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- Gemma 4 31B
- 47.9
- Supported · #104/181
- GPT-5.5 Pro
- 61.1
- Estimated · #36/181
- Basis
- BenchAlign lane · 4 vs 2 public rows
- Reading
- Directional only
Coding
Not comparable- Gemma 4 31B
- 43.5
- Supported · #123/183
- GPT-5.5 Pro
- Not ranked
- Basis
- BenchAlign lane · 2 vs 0 public rows
- Reading
- Not comparable
Reasoning
Not comparable- Gemma 4 31B
- 70.1
- Unranked · 2 rankable rows
- GPT-5.5 Pro
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- Gemma 4 31B
- Not ranked
- GPT-5.5 Pro
- 70.2
- Unranked · 3 rankable rows
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Gemma 4 31B
- Not ranked
- GPT-5.5 Pro
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Gemma 4 31B
- 58.4
- #30/48
- GPT-5.5 Pro
- Not ranked
- Basis
- Provisional lane · 1 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Gemma 4 31B
- 92.6
- #12/120
- GPT-5.5 Pro
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Gemma 4 31B | GPT-5.5 Pro | Basis | Reading |
|---|---|---|---|---|
| Agentic | 27.6Supported · #140/151 | 60.6Estimated · #24/151 | Directional onlyBenchAlign lane · 1 vs 1 public rows | Directional only |
| Knowledge | 47.9Supported · #104/181 | 61.1Estimated · #36/181 | Directional onlyBenchAlign lane · 4 vs 2 public rows | Directional only |
| Coding | 43.5Supported · #123/183 | Not ranked | Not comparableBenchAlign lane · 2 vs 0 public rows | Not comparable |
| Reasoning | 70.1Unranked · 2 rankable rows | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | Not ranked | 70.2Unranked · 3 rankable rows | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 58.4#30/48 | Not ranked | Not comparableProvisional lane · 1 vs 0 weighted rows | Not comparable |
| Instruction following | 92.6#12/120 | Not ranked | 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.
HLE
Knowledge
HLE w/o tools
Knowledge
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
- Gemma 4 31B
- Self-hosted; infrastructure cost varies
- Fits in one request
- GPT-5.5 Pro
- $0.12
- Fits in one request
Gemma 4 31B has no comparable published API token rate.
Repository review
50K fresh input + 3K output tokens
- Gemma 4 31B
- Self-hosted; infrastructure cost varies
- Fits in one request
- GPT-5.5 Pro
- $2.04
- Fits in one request
Gemma 4 31B has no comparable published API token rate.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Gemma 4 31B
- Self-hosted; infrastructure cost varies
- Fits in one request
- Cached-input rate unavailable
- GPT-5.5 Pro
- $8.40
- Fits in one request
- Cached input priced at the published list-input rate
GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate. Gemma 4 31B has no comparable published API token rate.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationGemma 4 31BGPT-5.5 Pro
Context window
Maximum documented context; output-token limits may be lower.
Gemma 4 31B
GPT-5.5 Pro
API model ID
Gemma 4 31B
gemma-4-31b-it
Google Gemma Gemini API guideGPT-5.5 Pro
gpt-5.5-pro
OpenAI GPT-5.5 Pro model documentationCached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Gemma 4 31B
No comparable hosted API rate
GPT-5.5 Pro
Not published
OpenAI pricingDocumented inputs
Gemma 4 31B
text, image
Google Gemma 4 model documentationGPT-5.5 Pro
text, image
OpenAI model catalogDocumented outputs
Gemma 4 31B
GPT-5.5 Pro
Provider availability
Gemma 4 31B
Generally Available · Gemini API, Google AI Studio, open weights
Google Gemma Gemini API guideGPT-5.5 Pro
Generally Available · OpenAI Responses API
OpenAI model catalogReasoning profile
Gemma 4 31B
Reasoning
GPT-5.5 Pro
Reasoning
Weight access
Gemma 4 31B
Open Weight
GPT-5.5 Pro
Proprietary
License
Gemma 4 31B
Open Weight
GPT-5.5 Pro
Proprietary
Release date
Gemma 4 31B
2026-04-02
GPT-5.5 Pro
2026-04-23
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-5.5 Pro has the higher public score estimate, 63.07 versus 58.69, but the 90% score intervals overlap.
- Workload cost
- A complete comparable API-rate estimate is not available for both models.
- 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.
Gemma 4 31B
API / mo$0
Self-host / mo$429
Break-even—
GPT-5.5 Pro
API / mo$157,500
Self-host / moNot listed
Break-even—
Proprietary model — self-hosting not applicable.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence12 rows
Agentic
Coding
Knowledge
Math
Multimodal
MMMU-Pro
Gemma 4 31B76.9%SourceGPT-5.5 Pro—Not directly comparable
Frequently asked questions
Which is better, Gemma 4 31B or GPT-5.5 Pro?
GPT-5.5 Pro has the higher public score estimate, 63.07 versus 58.69, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.
Which is better for coding, Gemma 4 31B or GPT-5.5 Pro?
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, Gemma 4 31B or GPT-5.5 Pro?
GPT-5.5 Pro scores higher for agentic tasks on the public lane, 60.6 to 27.6. GPT-5.5 Pro 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, Gemma 4 31B or GPT-5.5 Pro?
Both models do not have comparable published API token rates, so this page does not name a universal price winner.
Which has the larger context window, Gemma 4 31B or GPT-5.5 Pro?
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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