Claude Sonnet 5.5 vs Gemini 2.5 Pro Preview 06-05
Updated October 21, 2026. 2 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Claude Sonnet 5.5 scores 88.9 and Gemini 2.5 Pro Preview 06-05 83.1 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking.
Pick Claude Sonnet 5.5 when what matters is Humanity's Last Exam (Artificial Analysis run) or GPQA Diamond (Epoch AI run), where it leads; pick Gemini 2.5 Pro Preview 06-05 when the context window is larger, 1.05M against 1M tokens.
- Shared results
- 2
- Claude Sonnet 5.5 only
- 93
- Gemini 2.5 Pro Preview 06-05 only
- 12
- Like-for-like categories
- 1 of 9
Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.
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, four public coding benchmarks
No call
88.9 against 83.1, from different benchmarks with none in common.
Directional only
Intelligence
AA Intelligence Index
No call
Only Claude Sonnet 5.5 has a AA Intelligence Index result, 56.0.
Directional only
Web design
Design Arena: websites
No call
Only Claude Sonnet 5.5 has a Design Arena: websites result, 1326.
Directional only
General
Vals Index
No call
Only Claude Sonnet 5.5 has a Vals Index result, 70.8%.
Directional only
Long documents
Listed context window
Gemini 2.5 Pro Preview 06-05
Gemini 2.5 Pro Preview 06-05 takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 2.5 Pro Preview 06-05
Claude Sonnet 5.5 $0.0070, Gemini 2.5 Pro Preview 06-05 $0.0063 per turn.
List prices
At a glance
- Coding index
- Claude Sonnet 5.5 88.9 from 2 benchmarks, Gemini 2.5 Pro Preview 06-05 83.1 from 1 benchmark.
- Widest category
- Reasoning, 22.9 points apart on average over 2 shared benchmarks.
- Widest single gap
- Humanity's Last Exam (Artificial Analysis run): Claude Sonnet 5.5 55.0% against Gemini 2.5 Pro Preview 06-05 19.9%, 35.1 points apart on a 0 to 100 scale.
- Output price
- Both cost $10.00 per million output tokens.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, Gemini 2.5 Pro Preview 06-05 1.05M.
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 Sonnet 5.5 | Bars | Gemini 2.5 Pro Preview 06-05 | Ties |
|---|---|---|---|---|
| Reasoning | 2 | 0 | ||
| All shared boards | 2 | 0 |
CodingDirectional onlyFour of these boards feed the Vibe Coding Index23 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 83.1% | Only Gemini 2.5 Pro Preview 06-05 measured |
| LiveBench coding | 94.7% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev | 1768 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveCodeBench (Vals AI) | Not measured | 79.2% | Only Gemini 2.5 Pro Preview 06-05 measured |
| Terminal-Bench 4 (Vals AI) | 64.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vibe Code Bench (Vals AI) | 92.4% | Not measured | Only Claude Sonnet 5.5 measured |
| Code migration (Vals AI) | 69.8% | Not measured | Only Claude Sonnet 5.5 measured |
| ProgramBench (Vals AI) | 6.5% | Not measured | Only Claude Sonnet 5.5 measured |
| IOI (Vals AI) | 83.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench 2.1 (Vals AI) | 83.2% | Not measured | Only Claude Sonnet 5.5 measured |
| SWE-bench Multimodal (Vals AI) | 58.3% | Not measured | Only Claude Sonnet 5.5 measured |
| CyberBench (Vals AI) | 59.6% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 77.8% | Only Gemini 2.5 Pro Preview 06-05 measured |
| SciCode | 61.0% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierCode | 52.1% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierSWE | 61.9% | Not measured | Only Claude Sonnet 5.5 measured |
| GSO-Bench | Not measured | 3.9% | Only Gemini 2.5 Pro Preview 06-05 measured |
| ALE-Bench | 1819.1 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: coding | 1513 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: software and IT | 1504 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: React | 1817 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: HTML | 1741 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena WebDev: from an image | 1737 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 15 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | Not measured | Only Claude Sonnet 5.5 measured |
| Epoch Capabilities Index | 166.2 | Not measured | Only Claude Sonnet 5.5 measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index21 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1303 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building mobile apps | 1265 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1245 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench research | 83.6% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench browser | 84.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench long agentic | 78.8% | Not measured | Only Claude Sonnet 5.5 measured |
| SREBench (Vals AI) | 30.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Finance Agent (Vals AI) | 58.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Tax Agent Bench (Vals AI) | 42.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Legal Research Bench (Vals AI) | 48.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | 10.4% | Not measured | Only Claude Sonnet 5.5 measured |
| Excel Modeling Benchmark (Vals AI) | 75.7% | Not measured | Only Claude Sonnet 5.5 measured |
| BioMysteryBench (Vals AI) | 81.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench-Science (Vals AI) | 47.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Vals Science Index | 59.1% | Not measured | Only Claude Sonnet 5.5 measured |
| APEX-Agents | 75.5% | Not measured | Only Claude Sonnet 5.5 measured |
| METR time horizons | Not measured | 55.4% | Only Gemini 2.5 Pro Preview 06-05 measured |
| Remote Labor Index | Not measured | 0.8% | Only Gemini 2.5 Pro Preview 06-05 measured |
| DeepResearch Bench | Not measured | 42.8% | Only Gemini 2.5 Pro Preview 06-05 measured |
| SpireClimb | 1.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Vending-Bench 2 | $11,165 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 18 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| LiveBench reasoning | 91.6% | Not measured | Only Claude Sonnet 5.5 measured |
| MysteryMechanism (Vals AI) | 49.1% | Not measured | Only Claude Sonnet 5.5 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 83.6% | Only Gemini 2.5 Pro Preview 06-05 measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | 19.9% | Claude Sonnet 5.5 |
| GPQA Diamond (Epoch AI run) | 95.6% | 84.8% | Claude Sonnet 5.5 |
| SimpleBench | Not measured | 62.4% | Only Gemini 2.5 Pro Preview 06-05 measured |
| Chess puzzles | 59.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Mystery game puzzles | 65.0% | Not measured | Only Claude Sonnet 5.5 measured |
| VPCT | Not measured | 46.4% | Only Gemini 2.5 Pro Preview 06-05 measured |
| LMArena Text: hard prompts | 1494 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: expert | 1531 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: hard prompts in English | 1502 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: diagrams | 1329 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | 1331 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierMath, tiers 1 to 3 | 88.8% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierMath, tier 4 | 80.5% | Not measured | Only Claude Sonnet 5.5 measured |
| ProofBench | 100.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: math | 1497 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: mathematical work | 1510 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| MedCode (Vals AI) | 52.9% | Not measured | Only Claude Sonnet 5.5 measured |
| MMLU Pro (Artificial Analysis run) | Not measured | 85.8% | Only Gemini 2.5 Pro Preview 06-05 measured |
| SimpleQA Verified | 46.5% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: science | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: medicine and healthcare | 1464 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: legal and government | 1483 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: business and finance | 1468 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 10 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| Design Arena: websites | 1326 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: UI components | 1367 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: game dev | 1469 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: data viz | 1389 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: 3D | 1458 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: all code categories | 1364 | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench design | 85.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 2 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index27 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | Leader |
|---|---|---|---|
| Vals Index | 70.8% | Not measured | Only Claude Sonnet 5.5 measured |
| LiveBench data analysis | 59.5% | Not measured | Only Claude Sonnet 5.5 measured |
| Public Benefits Bench (Vals AI) | 67.2% | Not measured | Only Claude Sonnet 5.5 measured |
| SAGE (Vals AI) | 51.8% | Not measured | Only Claude Sonnet 5.5 measured |
| MedScribe (Vals AI) | 91.1% | Not measured | Only Claude Sonnet 5.5 measured |
| Long context reasoning (AA-LCR) | 82.7% | Not measured | Only Claude Sonnet 5.5 measured |
| DTBench | 97.3% | Not measured | Only Claude Sonnet 5.5 measured |
| LMCA | 68.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Fiction.LiveBench | Not measured | 91.7% | Only Gemini 2.5 Pro Preview 06-05 measured |
| Furniture assembly | 75.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text | 1473 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: instruction following | 1492 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: creative writing | 1467 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision | 1287 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1484 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: non-English | 1456 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Chinese | 1535 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: French | 1499 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Spanish | 1451 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: Russian | 1454 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: multi-turn | 1465 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: longer queries | 1495 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: writing and language | 1474 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: entertainment and media | 1461 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: English | 1289 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: reading text | 1297 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: creative writing | 1242 | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | Gemini 2.5 Pro Preview 06-05 | 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
Gemini 2.5 Pro Preview 06-05 costs less
Repository review
50K input + 3K output tokens
Gemini 2.5 Pro Preview 06-05 costs less
Agent loop
200K input + 10K output tokens
Gemini 2.5 Pro Preview 06-05 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 Sonnet 5.5 | Google Gemini 2.5 Pro Preview 06-05 |
|---|---|---|
| Maker | Anthropic | |
| Weights | No public weights listed | No public weights listed |
| Released | September 28, 2026 | June 5, 2025 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $2.00 | $1.25 |
| Output $/Mtok | $10.00 | $10.00 |
| Coding index | 88.9 | 83.1 |
| Independent measurements behind it | 2 | 1 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than Gemini 2.5 Pro Preview 06-05 for coding?
Claude Sonnet 5.5 scores 88.9 and Gemini 2.5 Pro Preview 06-05 83.1 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking. Pick Claude Sonnet 5.5 when what matters is Humanity's Last Exam (Artificial Analysis run) or GPQA Diamond (Epoch AI run), where it leads; pick Gemini 2.5 Pro Preview 06-05 when the context window is larger, 1.05M against 1M tokens.
Which is cheaper, Claude Sonnet 5.5 or Gemini 2.5 Pro Preview 06-05?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Gemini 2.5 Pro Preview 06-05 costs $1.25 and $10.00. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Sonnet 5.5 or Gemini 2.5 Pro Preview 06-05?
Gemini 2.5 Pro Preview 06-05, with 1.05M tokens against 1M.
How many benchmarks is the Claude Sonnet 5.5 vs Gemini 2.5 Pro Preview 06-05 comparison based on?
2 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 2 independent benchmarks and Gemini 2.5 Pro Preview 06-05's on 1. Where only one model has a result, the page says so instead of naming a winner.