Claude Opus 5.5 vs Gemma 4 31B
Claude Opus 5.5 leads Gemma 4 31B on coding, 88.8 to 39.0 on the Vibe Coding Index, and Gemma 4 31B costs 50.0x less per output token ($0.40 vs $20.00 per million). Updated October 22, 2026; 54 benchmarks have a result for both.
vs boards won of 54 shared
Claude Opus 5.5 or Gemma 4 31B: which to pick
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 39.0 for Gemma 4 31B.
Pick Gemma 4 31B for output tokens 50.0x cheaper ($0.40 vs $20.00 per million) and work measured by SAGE (Vals AI), where it leads.
Model AClaude Opus 5.5Anthropic88.8/1005 independent benchmarksNo cost per solved taskModel BGemma 4 31BGoogle39.0/1002 independent benchmarksNo cost per solved task
- Shared results
- 54
- Claude Opus 5.5 only
- 55
- Gemma 4 31B only
- 17
- Like-for-like categories
- 8 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
Claude Opus 5.5
Claude Opus 5.5 scores 88.8 against 39.0.
5 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Opus 5.5
Claude Opus 5.5 leads, 57.6 against 14.7.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Gemma 4 31B has a AA Agentic Index result, 4.2.
Directional only
Web design
Design Arena: websites
No call
Only Claude Opus 5.5 has a Design Arena: websites result, 1335.
Directional only
General
Vals Index
No call
Only Claude Opus 5.5 has a Vals Index result, 70.2%.
Directional only
Long documents
Listed context window
Claude Opus 5.5
Claude Opus 5.5 takes 1M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemma 4 31B
Claude Opus 5.5 $0.014, Gemma 4 31B $0.0003 per turn.
List prices
At a glance
- Coding index
- Claude Opus 5.5 88.8 from 5 benchmarks, Gemma 4 31B 39.0 from 2 benchmarks.
- Widest category
- Agentic work, 62.8 points apart on average over 3 shared benchmarks.
- Widest single gap
- LiveBench browser: Claude Opus 5.5 80.0% against Gemma 4 31B 4.0%, 76.0 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 5.5 $20.00 against Gemma 4 31B $0.40 per million output tokens, 50.0x apart.
- Context window
- Claude Opus 5.5 takes 1M tokens, Gemma 4 31B 262K.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Claude Opus 5.5 | Bars | Gemma 4 31B | Ties |
|---|---|---|---|---|
| Coding | 9 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 3 | 0 | ||
| Reasoning | 8 | 0 | ||
| Math | 3 | 0 | ||
| Knowledge | 6 | 0 | ||
| Web design | 1 | 0 | ||
| General | 21 | 1 | ||
| All shared boards | 53 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index90
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| LiveBench coding | 96.3% | 49.0% | Claude Opus 5.5 |
| LMArena WebDev | 1807 | 1367 | Claude Opus 5.5 |
| AA Coding Index | Not measured | 43.4 | Only Gemma 4 31B measured |
| Terminal-Bench 4 (Vals AI) | 65.2% | Not measured | Only Claude Opus 5.5 measured |
| Vibe Code Bench (Vals AI) | 90.3% | Not measured | Only Claude Opus 5.5 measured |
| Code migration (Vals AI) | 66.7% | Not measured | Only Claude Opus 5.5 measured |
| ProgramBench (Vals AI) | 18.5% | Not measured | Only Claude Opus 5.5 measured |
| IOI (Vals AI) | 95.1% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 87.6% | Not measured | Only Claude Opus 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| Vibe Code Bench 1-100 (Vals AI) | 30.4% | Not measured | Only Claude Opus 5.5 measured |
| CyberBench (Vals AI) | 74.6% | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 66.9% | 45.5% | Claude Opus 5.5 |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 36.4% | Only Gemma 4 31B measured |
| FrontierCode | 54.6% | Not measured | Only Claude Opus 5.5 measured |
| FrontierSWE | 62.3% | Not measured | Only Claude Opus 5.5 measured |
| WeirdML | Not measured | 52.3% | Only Gemma 4 31B measured |
| MirrorCode | 77.4% | Not measured | Only Claude Opus 5.5 measured |
| ALE-Bench | 2147.4 | 925.5 | Claude Opus 5.5 |
| LMArena Text: coding | 1545 | 1459 | Claude Opus 5.5 |
| LMArena Text: software and IT | 1538 | 1463 | Claude Opus 5.5 |
| LMArena WebDev: React | 1855 | 1359 | Claude Opus 5.5 |
| LMArena WebDev: HTML | 1753 | 1380 | Claude Opus 5.5 |
| LMArena WebDev: from an image | 1753 | Not measured | Only Claude Opus 5.5 measured |
| SciCode | 18.5% | 8.9% | Claude Opus 5.5 |
| Neither model has a result on the other 14 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| AA Intelligence Index | 57.6 | 14.7 | Claude Opus 5.5 |
| Epoch Capabilities Index | 168.8 | 143.0 | Claude Opus 5.5 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 4.2 | Only Gemma 4 31B measured |
| Design Arena: agents building web apps | 1316 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: agents building mobile apps | 1308 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: spreadsheets | 1368 | Not measured | Only Claude Opus 5.5 measured |
| LiveBench research | 85.0% | 44.4% | Claude Opus 5.5 |
| LiveBench browser | 80.0% | 4.0% | Claude Opus 5.5 |
| LiveBench long agentic | 85.0% | 13.3% | Claude Opus 5.5 |
| SREBench (Vals AI) | 33.6% | Not measured | Only Claude Opus 5.5 measured |
| Finance Agent (Vals AI) | 58.6% | Not measured | Only Claude Opus 5.5 measured |
| Tax Agent Bench (Vals AI) | 45.6% | Not measured | Only Claude Opus 5.5 measured |
| Legal Research Bench (Vals AI) | 50.5% | Not measured | Only Claude Opus 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 9.2% | Not measured | Only Claude Opus 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.9% | Not measured | Only Claude Opus 5.5 measured |
| BioMysteryBench (Vals AI) | 79.3% | Not measured | Only Claude Opus 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Opus 5.5 measured |
| Vals Science Index | 58.7% | Not measured | Only Claude Opus 5.5 measured |
| Time Horizon Index (Vals AI) | 91.3% | Not measured | Only Claude Opus 5.5 measured |
| CUA-bench (Vals AI) | 14.0% | Not measured | Only Claude Opus 5.5 measured |
| Robo-bench (Vals AI) | 14.6% | Not measured | Only Claude Opus 5.5 measured |
| τ²-Bench Telecom | Not measured | 65.5% | Only Gemma 4 31B measured |
| APEX-Agents | 73.5% | Not measured | Only Claude Opus 5.5 measured |
| Remote Labor Index | 21.3% | Not measured | Only Claude Opus 5.5 measured |
| SpireClimb | 3.3% | Not measured | Only Claude Opus 5.5 measured |
| Vending-Bench 2 | $9,235 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Search | 1213 | Not measured | Only Claude Opus 5.5 measured |
| Neither model has a result on the other 16 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| LiveBench reasoning | 92.2% | 68.3% | Claude Opus 5.5 |
| MysteryMechanism (Vals AI) | 49.5% | Not measured | Only Claude Opus 5.5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 85.7% | Only Gemma 4 31B measured |
| Humanity's Last Exam (Artificial Analysis run) | 61.4% | 23.6% | Claude Opus 5.5 |
| GPQA Diamond (Epoch AI run) | 90.6% | 75.8% | Claude Opus 5.5 |
| ARC-AGI | 98.5% | Not measured | Only Claude Opus 5.5 measured |
| ARC-AGI-2 | 93.3% | Not measured | Only Claude Opus 5.5 measured |
| Chess puzzles | 67.0% | Not measured | Only Claude Opus 5.5 measured |
| Mystery game puzzles | 71.0% | Not measured | Only Claude Opus 5.5 measured |
| EBR-bench | 71.4% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: hard prompts | 1536 | 1448 | Claude Opus 5.5 |
| LMArena Text: expert | 1549 | 1464 | Claude Opus 5.5 |
| LMArena Text: hard prompts in English | 1535 | 1456 | Claude Opus 5.5 |
| LMArena Vision: diagrams | 1345 | 1283 | Claude Opus 5.5 |
| LMArena Vision: homework | 1362 | 1310 | Claude Opus 5.5 |
| Kagi LLM Benchmark | Not measured | 63.5% | Only Gemma 4 31B measured |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | 73.3% | Claude Opus 5.5 |
| FrontierMath, tiers 1 to 3 | 91.2% | Not measured | Only Claude Opus 5.5 measured |
| FrontierMath, tier 4 | 95.0% | Not measured | Only Claude Opus 5.5 measured |
| ProofBench | 100.0% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: math | 1518 | 1463 | Claude Opus 5.5 |
| LMArena Text: mathematical work | 1516 | 1465 | Claude Opus 5.5 |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| CaseLaw (Vals AI) | Not measured | 52.6% | Only Gemma 4 31B measured |
| MortgageTax (Vals AI) | Not measured | 61.4% | Only Gemma 4 31B measured |
| MedCode (Vals AI) | 49.8% | Not measured | Only Claude Opus 5.5 measured |
| SimpleQA Verified | 72.2% | 10.4% | Claude Opus 5.5 |
| LMArena Text: science | 1524 | 1457 | Claude Opus 5.5 |
| LMArena Text: medicine and healthcare | 1509 | 1451 | Claude Opus 5.5 |
| LMArena Text: legal and government | 1518 | 1438 | Claude Opus 5.5 |
| LMArena Text: business and finance | 1494 | 1430 | Claude Opus 5.5 |
| FACTS Benchmark Suite | 65.3% | 45.3% | Claude Opus 5.5 |
| Neither model has a result on the other 9 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| Design Arena: websites | 1335 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: UI components | 1385 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: game dev | 1461 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: data viz | 1397 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: 3D | 1476 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: all code categories | 1390 | Not measured | Only Claude Opus 5.5 measured |
| Design Arena: SVG | 1329 | Not measured | Only Claude Opus 5.5 measured |
| LiveBench design | 86.9% | 58.4% | Claude Opus 5.5 |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index211
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| Vals Index | 70.2% | Not measured | Only Claude Opus 5.5 measured |
| LiveBench data analysis | 80.3% | 53.3% | Claude Opus 5.5 |
| Public Benefits Bench (Vals AI) | 70.6% | Not measured | Only Claude Opus 5.5 measured |
| SAGE (Vals AI) | 45.8% | 55.0% | Gemma 4 31B |
| MedScribe (Vals AI) | 91.4% | Not measured | Only Claude Opus 5.5 measured |
| IFBench | Not measured | 75.6% | Only Gemma 4 31B measured |
| Long context reasoning (AA-LCR) | 84.7% | 69.7% | Claude Opus 5.5 |
| DTBench | 98.9% | 82.7% | Claude Opus 5.5 |
| LMCA | 68.2% | 39.3% | Claude Opus 5.5 |
| Surface Evolver Bench | Not measured | 30.6% | Only Gemma 4 31B measured |
| Furniture assembly | 83.3% | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text | 1516 | 1443 | Claude Opus 5.5 |
| LMArena Text: instruction following | 1537 | 1433 | Claude Opus 5.5 |
| LMArena Text: creative writing | 1535 | 1417 | Claude Opus 5.5 |
| LMArena Vision | 1321 | 1276 | Claude Opus 5.5 |
| LMArena Text: English | 1519 | 1451 | Claude Opus 5.5 |
| LMArena Text: non-English | 1507 | 1430 | Claude Opus 5.5 |
| LMArena Text: Chinese | 1582 | 1475 | Claude Opus 5.5 |
| LMArena Text: Japanese | 1534 | Not measured | Only Claude Opus 5.5 measured |
| LMArena Text: French | 1493 | 1436 | Claude Opus 5.5 |
| LMArena Text: Spanish | 1508 | 1442 | Claude Opus 5.5 |
| LMArena Text: Russian | 1517 | 1460 | Claude Opus 5.5 |
| LMArena Text: Polish | Not measured | 1433 | Only Gemma 4 31B measured |
| LMArena Text: multi-turn | 1501 | 1452 | Claude Opus 5.5 |
| LMArena Text: longer queries | 1532 | 1446 | Claude Opus 5.5 |
| LMArena Text: writing and language | 1532 | 1432 | Claude Opus 5.5 |
| LMArena Text: entertainment and media | 1515 | 1405 | Claude Opus 5.5 |
| LMArena Vision: English | 1317 | 1271 | Claude Opus 5.5 |
| LMArena Vision: Chinese | Not measured | 1326 | Only Gemma 4 31B measured |
| LMArena Vision: reading text | 1326 | 1282 | Claude Opus 5.5 |
| LMArena Vision: humor | Not measured | 1280 | Only Gemma 4 31B measured |
| LMArena Vision: captioning | Not measured | 1218 | Only Gemma 4 31B measured |
| LMArena Vision: recognizing things | Not measured | 1226 | Only Gemma 4 31B measured |
| LMArena Vision: creative writing | 1320 | 1285 | Claude Opus 5.5 |
| LMArena Document | Not measured | 1425 | Only Gemma 4 31B measured |
| Neither model has a result on the other 11 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 5.5 | Gemma 4 31B | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Claude Opus 5.5$0.014Fits in one request
Gemma 4 31B$0.0003Fits in one request
Gemma 4 31B costs less
Repository review
50K input + 3K output tokens
Claude Opus 5.5$0.260Fits in one request
Gemma 4 31B$0.0082Fits in one request
Gemma 4 31B costs less
Agent loop
200K input + 10K output tokens
Claude Opus 5.5$1.00Fits in one request
Gemma 4 31B$0.032Fits in one request
Gemma 4 31B costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Anthropic Claude Opus 5.5 | Google Gemma 4 31B |
|---|---|---|
| Maker | Anthropic | |
| Weights | No public weights listed | Open weights |
| Released | September 22, 2026 | April 2, 2026 |
| Context window | 1M | 262K |
| Input $/Mtok | $4.00 | $0.14 |
| Output $/Mtok | $20.00 | $0.40 |
| Coding index | 88.8 | 39.0 |
| Independent measurements behind it | 5 | 2 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 5.5 better than Gemma 4 31B for coding?
Pick Claude Opus 5.5 for coding: it scores 88.8 on the Vibe Coding Index against 39.0 for Gemma 4 31B. Pick Gemma 4 31B for output tokens 50.0x cheaper ($0.40 vs $20.00 per million) and work measured by SAGE (Vals AI), where it leads.
Which is cheaper, Claude Opus 5.5 or Gemma 4 31B?
Claude Opus 5.5 costs $4.00 per million input tokens and $20.00 per million output tokens; Gemma 4 31B costs $0.14 and $0.40. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Opus 5.5 or Gemma 4 31B?
Claude Opus 5.5, with 1M tokens against 262K.
How many benchmarks is the Claude Opus 5.5 vs Gemma 4 31B comparison based on?
54 benchmarks have a result for both models as of October 22, 2026. Claude Opus 5.5's coding index rests on 5 independent benchmarks and Gemma 4 31B's on 2. Where only one model has a result, the page says so instead of naming a winner.