Skip to content
ModelCap

Head-to-head comparison

Claude Sonnet 5.5 vs Gemma 4 31B

Claude Sonnet 5.5 (Anthropic) and Gemma 4 31B (Google) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 2 October 2026

As of 2 October 2026, Claude Sonnet 5.5 holds the stronger ModelCap Index position (#5 vs #28); Gemma 4 31B is 29.4× cheaper per output token ($0.34/1M vs $10.00/1M); Claude Sonnet 5.5 offers the longer context window (1M vs 262K tokens); and Gemma 4 31B ships open weights.

Which should you choose?

Choose Claude Sonnet 5.5 if…

  • you want the stronger overall ModelCap Index position — #5 against #28 (82.4 vs 71.8 points).
  • you need the longer context window — 1M tokens against 262K.
  • Arena text is your yardstick — 1471 against 1453.
  • AA Humanity's Last Exam is your yardstick — 55.0% against 11.8%.
  • you want the more recently listed model — Claude Sonnet 5.5 was listed 28 September 2026, Gemma 4 31B 2 April 2026.

Choose Gemma 4 31B if…

  • API cost matters — $0.34/1M output tokens against $10.00/1M, about 29.4× cheaper.
  • your workload is prompt-heavy — input tokens cost $0.09/1M against $2.00/1M.
  • you want to self-host: Gemma 4 31B ships open weights while Claude Sonnet 5.5 is no linked weights.
  • you want provider choice — 13 listed API providers against 5.

Claude Sonnet 5.5 vs Gemma 4 31B: specs, pricing and context

Specification comparison of Claude Sonnet 5.5 and Gemma 4 31B
FieldClaude Sonnet 5.5AnthropicGemma 4 31BGoogle
ModelCap Index position#5#28
Index score82.471.8
EvidenceMeasuredMeasured
Input price / 1M tokens$2.00$0.09
Output price / 1M tokens$10.00$0.34
Context window1M tokens262K tokens
Declared route output cap128K16K
API providers listed513
Weight accessNo linked weightsOpen weights
Input modalitiesText, Image, FileImage, Text, Video
First listed28 September 20262 April 2026
PublisherAnthropicGoogle

Evidence: 2 public benchmark observations across 2 boards · 3 public benchmark observations across 3 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Claude Sonnet 5.5 vs Gemma 4 31B

Public benchmark boards where Claude Sonnet 5.5 or Gemma 4 31B has a published result
BoardClaude Sonnet 5.5Gemma 4 31BLeads
Arena textArena (LMArena)14711461–1481X-High14531445–1460Not reportedClaude Sonnet 5.5
Arena codingArena (LMArena)—15021487–1517Only one result
AA Intelligence IndexArtificial Analysis56.0Reasoning—Only one result
AA Terminal-Bench 2.1Artificial Analysis—29.2%Non-reasoningOnly one result
AA τ²-Bench TelecomArtificial Analysis—65.5%Non-reasoningOnly one result
AA Humanity's Last ExamArtificial Analysis55.0%Adaptive Reasoning, Max Effort, Default Fallback11.8%Non-reasoningClaude Sonnet 5.5
WildClawBench OpenClawWildClawBench—37.6Only one result

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Claude Sonnet 5.5 vs Gemma 4 31B: common questions

Is Claude Sonnet 5.5 better than Gemma 4 31B?

Claude Sonnet 5.5 ranks higher on the ModelCap Index as of 2 October 2026: #5 against #28. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it. Their published uncertainty intervals overlap, so the rank difference alone does not establish a reliable capability advantage for your workload.

Is Claude Sonnet 5.5 cheaper than Gemma 4 31B?

Gemma 4 31B is cheaper on output tokens: $0.34/1M against $10.00/1M. Input tokens are $2.00/1M for Claude Sonnet 5.5 and $0.09/1M for Gemma 4 31B. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $9.00 for Claude Sonnet 5.5 versus $0.35 for Gemma 4 31B. Gemma 4 31B costs 96.1% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.

Which has the bigger context window, Claude Sonnet 5.5 or Gemma 4 31B?

Claude Sonnet 5.5 has the larger context window: 1M tokens against 262K. OpenRouter catalogue or provider-endpoint declaration. Limits can vary by provider and prompt length; a model-wide maximum has not been independently verified.

Which is better for coding, Claude Sonnet 5.5 or Gemma 4 31B?

The two models do not share a coding benchmark board on ModelCap yet, so no head-to-head coding score is published; the ModelCap Index position is the closest overall signal.

Are Claude Sonnet 5.5 and Gemma 4 31B open-weight models?

Claude Sonnet 5.5: No linked weights. Gemma 4 31B: Open weights. Open weights mean the checkpoint can be downloaded and self-hosted under its licence. A missing weight link does not identify every API or chat product that offers a model.

Where can I run Claude Sonnet 5.5 and Gemma 4 31B?

ModelCap currently lists 5 API providers for Claude Sonnet 5.5 and 13 for Gemma 4 31B, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Claude Sonnet 5.5 vs Gemma 4 31B comparison?

Every figure and ModelCap Index position comes from the same published snapshot dated 2 October 2026. Publication and page updates happen separately; use the snapshot date shown on the page.

Explore further