Claude Opus 4.1 vs Gemini 3.8 Flash
Updated October 21, 2026. 58 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
vs boards won of 58 shared
Decision reading
Pick Gemini 3.8 Flash for coding: it scores 70.5 on the Vibe Coding Index against 27.2 for Claude Opus 4.1.
Claude Opus 4.1 is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Model AClaude Opus 4.1Anthropic27.2/1001 independent benchmarkNo cost per solved taskModel BGemini 3.8 FlashGoogle70.5/1002 independent benchmarks$2.74 per solved task
- Shared results
- 58
- Claude Opus 4.1 only
- 13
- Gemini 3.8 Flash only
- 68
- Like-for-like categories
- 7 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
Gemini 3.8 Flash
Gemini 3.8 Flash scores 70.5 against 27.2.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 40.9 against 22.8.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Gemini 3.8 Flash has a AA Agentic Index result, 40.2.
Directional only
Reasoning
GPQA Diamond
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 94.4% against 76.3%.
Same board, both measured
Math
AIME
No call
Only Claude Opus 4.1 has a AIME result, 78.2%.
Directional only
Knowledge
MMLU Pro
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 90.2% against 87.9%.
Same board, both measured
Web design
Design Arena: websites
Gemini 3.8 Flash
Gemini 3.8 Flash leads, 1301 against 1177.
Same board, both measured
General
Vals Index
No call
Only Gemini 3.8 Flash has a Vals Index result, 56.0%.
Directional only
Long documents
Listed context window
Gemini 3.8 Flash
Gemini 3.8 Flash takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.8 Flash
Claude Opus 4.1 $0.052, Gemini 3.8 Flash $0.0029 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.8 Flash has the number, $2.74.
Directional only
At a glance
- Coding index
- Claude Opus 4.1 27.2 from 1 benchmark, Gemini 3.8 Flash 70.5 from 2 benchmarks.
- Widest category
- Math, 27.3 points apart on average over 5 shared benchmarks.
- Widest single gap
- FrontierMath, tiers 1 to 3: Claude Opus 4.1 12.6% against Gemini 3.8 Flash 68.4%, 55.8 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.1 $75.00 against Gemini 3.8 Flash $4.125 per million output tokens, 18.2x apart.
- Context window
- Claude Opus 4.1 takes 200K tokens, Gemini 3.8 Flash 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 Opus 4.1 | Bars | Gemini 3.8 Flash | Ties |
|---|---|---|---|---|
| Coding | 0 | 6 | ||
| Intelligence | 0 | 2 | ||
| Reasoning | 0 | 7 | ||
| Math | 0 | 5 | ||
| Knowledge | 0 | 9 | ||
| Web design | 0 | 8 | ||
| General | 0 | 21 | ||
| All shared boards | 0 | 58 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index06
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 82.2% | Only Gemini 3.8 Flash measured |
| LMArena WebDev | 1390 | 1585 | Gemini 3.8 Flash |
| AA Coding Index | Not measured | 76.3 | Only Gemini 3.8 Flash measured |
| LiveCodeBench (Vals AI) | 66.5% | 89.5% | Gemini 3.8 Flash |
| SWE-bench Verified (Vals AI) | Not measured | 80.0% | Only Gemini 3.8 Flash measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 19.7% | Only Gemini 3.8 Flash measured |
| Vibe Code Bench (Vals AI) | Not measured | 78.7% | Only Gemini 3.8 Flash measured |
| Code migration (Vals AI) | Not measured | 36.5% | Only Gemini 3.8 Flash measured |
| ProgramBench (Vals AI) | Not measured | 1.0% | Only Gemini 3.8 Flash measured |
| IOI (Vals AI) | Not measured | 56.9% | Only Gemini 3.8 Flash measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 81.3% | Only Gemini 3.8 Flash measured |
| SWE-bench Multimodal (Vals AI) | Not measured | 40.8% | Only Gemini 3.8 Flash measured |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 18.8% | Only Gemini 3.8 Flash measured |
| SkillsBench (Vals AI) | Not measured | 58.0% | Only Gemini 3.8 Flash measured |
| CyberBench (Vals AI) | Not measured | 43.8% | Only Gemini 3.8 Flash measured |
| SciCode | Not measured | 56.6% | Only Gemini 3.8 Flash measured |
| Terminal-Bench | 38.0% | Not measured | Only Claude Opus 4.1 measured |
| FrontierCode | Not measured | 41.2% | Only Gemini 3.8 Flash measured |
| FrontierSWE | Not measured | 19.6% | Only Gemini 3.8 Flash measured |
| WeirdML | 45.9% | 84.8% | Gemini 3.8 Flash |
| Cybench | 42.0% | Not measured | Only Claude Opus 4.1 measured |
| ALE-Bench | Not measured | 1269.7 | Only Gemini 3.8 Flash measured |
| LMArena Text: coding | 1479 | 1508 | Gemini 3.8 Flash |
| LMArena Text: software and IT | 1456 | 1507 | Gemini 3.8 Flash |
| LMArena WebDev: React | Not measured | 1577 | Only Gemini 3.8 Flash measured |
| LMArena WebDev: HTML | 1399 | 1616 | Gemini 3.8 Flash |
| LMArena WebDev: from an image | Not measured | 1593 | Only Gemini 3.8 Flash measured |
| Neither model has a result on the other 11 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.8 | 40.9 | Gemini 3.8 Flash |
| Epoch Capabilities Index | 144.1 | 157.4 | Gemini 3.8 Flash |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index28 boards, none shared
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 40.2 | Only Gemini 3.8 Flash measured |
| Design Arena: agents building web apps | Not measured | 1238 | Only Gemini 3.8 Flash measured |
| Design Arena: agents building full-stack apps | Not measured | 1244 | Only Gemini 3.8 Flash measured |
| Design Arena: agents building mobile apps | Not measured | 1236 | Only Gemini 3.8 Flash measured |
| Design Arena: agents building Android apps | Not measured | 1078 | Only Gemini 3.8 Flash measured |
| Design Arena: agents building Godot games | Not measured | 1273 | Only Gemini 3.8 Flash measured |
| Design Arena: PowerPoint slides | Not measured | 1178 | Only Gemini 3.8 Flash measured |
| Design Arena: spreadsheets | Not measured | 1052 | Only Gemini 3.8 Flash measured |
| LiveBench research | Not measured | 79.1% | Only Gemini 3.8 Flash measured |
| LiveBench browser | Not measured | 64.0% | Only Gemini 3.8 Flash measured |
| LiveBench long agentic | Not measured | 30.1% | Only Gemini 3.8 Flash measured |
| SREBench (Vals AI) | Not measured | 11.1% | Only Gemini 3.8 Flash measured |
| Finance Agent (Vals AI) | Not measured | 61.4% | Only Gemini 3.8 Flash measured |
| Tax Agent Bench (Vals AI) | Not measured | 32.1% | Only Gemini 3.8 Flash measured |
| Legal Research Bench (Vals AI) | Not measured | 38.9% | Only Gemini 3.8 Flash measured |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 12.1% | Only Gemini 3.8 Flash measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 72.2% | Only Gemini 3.8 Flash measured |
| BioMysteryBench (Vals AI) | Not measured | 62.2% | Only Gemini 3.8 Flash measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 8.6% | Only Gemini 3.8 Flash measured |
| Vals Science Index | Not measured | 35.8% | Only Gemini 3.8 Flash measured |
| Time Horizon Index (Vals AI) | Not measured | 18.8% | Only Gemini 3.8 Flash measured |
| CUA-bench (Vals AI) | Not measured | 4.2% | Only Gemini 3.8 Flash measured |
| APEX-Agents | Not measured | 64.3% | Only Gemini 3.8 Flash measured |
| METR time horizons | 66.8% | Not measured | Only Claude Opus 4.1 measured |
| Remote Labor Index | Not measured | 5.8% | Only Gemini 3.8 Flash measured |
| GDPval | 43.6% | Not measured | Only Claude Opus 4.1 measured |
| DeepResearch Bench | 48.3% | Not measured | Only Claude Opus 4.1 measured |
| Vending-Bench 2 | Not measured | $5,094 | Only Gemini 3.8 Flash measured |
| Neither model has a result on the other 11 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index07
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| GPQA Diamond | 76.3% | 94.4% | Gemini 3.8 Flash |
| LiveBench reasoning | Not measured | 89.3% | Only Gemini 3.8 Flash measured |
| MysteryMechanism (Vals AI) | Not measured | 36.5% | Only Gemini 3.8 Flash measured |
| MMMU Pro (Vals AI) | 77.5% | 89.1% | Gemini 3.8 Flash |
| GPQA Diamond (Artificial Analysis run) | Not measured | 95.3% | Only Gemini 3.8 Flash measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 47.8% | Only Gemini 3.8 Flash measured |
| GPQA Diamond (Epoch AI run) | 77.3% | 95.4% | Gemini 3.8 Flash |
| ARC-AGI | Not measured | 98.5% | Only Gemini 3.8 Flash measured |
| ARC-AGI-2 | Not measured | 89.2% | Only Gemini 3.8 Flash measured |
| SimpleBench | 60.0% | Not measured | Only Claude Opus 4.1 measured |
| Chess puzzles | Not measured | 58.0% | Only Gemini 3.8 Flash measured |
| Mystery game puzzles | 21.0% | 47.0% | Gemini 3.8 Flash |
| EBR-bench | 7.9% | Not measured | Only Claude Opus 4.1 measured |
| VPCT | 35.0% | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts | 1442 | 1509 | Gemini 3.8 Flash |
| LMArena Text: expert | 1438 | 1526 | Gemini 3.8 Flash |
| LMArena Text: hard prompts in English | 1451 | 1504 | Gemini 3.8 Flash |
| LMArena Vision: diagrams | Not measured | 1345 | Only Gemini 3.8 Flash measured |
| LMArena Vision: homework | Not measured | 1351 | Only Gemini 3.8 Flash measured |
| Neither model has a result on the other 2 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index05
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| AIME | 78.2% | Not measured | Only Claude Opus 4.1 measured |
| MATH 500 (Vals AI) | 95.4% | Not measured | Only Claude Opus 4.1 measured |
| MGSM (Vals AI) | 94.4% | Not measured | Only Claude Opus 4.1 measured |
| OTIS Mock AIME | 68.9% | 98.9% | Gemini 3.8 Flash |
| FrontierMath, tiers 1 to 3 | 12.6% | 68.4% | Gemini 3.8 Flash |
| FrontierMath, tier 4 | 2.4% | 22.0% | Gemini 3.8 Flash |
| ProofBench | Not measured | 48.0% | Only Gemini 3.8 Flash measured |
| LMArena Text: math | 1431 | 1532 | Gemini 3.8 Flash |
| LMArena Text: mathematical work | 1434 | 1519 | Gemini 3.8 Flash |
| Neither model has a result on the other 4 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index09
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| MMLU Pro | 87.9% | 90.2% | Gemini 3.8 Flash |
| LegalBench (Vals AI) | 83.5% | 87.0% | Gemini 3.8 Flash |
| TaxEval (Vals AI) | 73.7% | 74.5% | Gemini 3.8 Flash |
| MortgageTax (Vals AI) | 61.1% | 65.3% | Gemini 3.8 Flash |
| MedQA (Vals AI) | 93.6% | Not measured | Only Claude Opus 4.1 measured |
| MedCode (Vals AI) | 47.2% | 48.1% | Gemini 3.8 Flash |
| SimpleQA Verified | Not measured | 69.7% | Only Gemini 3.8 Flash measured |
| LMArena Text: science | 1422 | 1523 | Gemini 3.8 Flash |
| LMArena Text: medicine and healthcare | 1416 | 1508 | Gemini 3.8 Flash |
| LMArena Text: legal and government | 1421 | 1497 | Gemini 3.8 Flash |
| LMArena Text: business and finance | 1406 | 1479 | Gemini 3.8 Flash |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index08
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| Design Arena: websites | 1177 | 1301 | Gemini 3.8 Flash |
| Design Arena: UI components | 1164 | 1318 | Gemini 3.8 Flash |
| Design Arena: game dev | 1172 | 1305 | Gemini 3.8 Flash |
| Design Arena: data viz | 1166 | 1269 | Gemini 3.8 Flash |
| Design Arena: 3D | 1153 | 1295 | Gemini 3.8 Flash |
| Design Arena: all code categories | 1171 | 1304 | Gemini 3.8 Flash |
| Design Arena: SVG | 1152 | 1295 | Gemini 3.8 Flash |
| Design Arena: ASCII art | 1167 | 1264 | Gemini 3.8 Flash |
| LiveBench design | Not measured | 72.7% | Only Gemini 3.8 Flash measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index021
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | Leader |
|---|---|---|---|
| Vals Index | Not measured | 56.0% | Only Gemini 3.8 Flash measured |
| LiveBench data analysis | Not measured | 54.0% | Only Gemini 3.8 Flash measured |
| Public Benefits Bench (Vals AI) | Not measured | 65.3% | Only Gemini 3.8 Flash measured |
| SAGE (Vals AI) | 31.4% | 35.1% | Gemini 3.8 Flash |
| MedScribe (Vals AI) | 73.9% | 84.5% | Gemini 3.8 Flash |
| Long context reasoning (AA-LCR) | Not measured | 84.0% | Only Gemini 3.8 Flash measured |
| DTBench | 80.0% | 95.7% | Gemini 3.8 Flash |
| LMCA | 37.1% | 52.9% | Gemini 3.8 Flash |
| Creative writing (Lech Mazur) | 84.7% | Not measured | Only Claude Opus 4.1 measured |
| Surface Evolver Bench | Not measured | 76.9% | Only Gemini 3.8 Flash measured |
| Furniture assembly | Not measured | 31.7% | Only Gemini 3.8 Flash measured |
| LMArena Text | 1419 | 1499 | Gemini 3.8 Flash |
| LMArena Text: instruction following | 1435 | 1492 | Gemini 3.8 Flash |
| LMArena Text: creative writing | 1412 | 1488 | Gemini 3.8 Flash |
| LMArena Vision | Not measured | 1315 | Only Gemini 3.8 Flash measured |
| LMArena Text: English | 1433 | 1498 | Gemini 3.8 Flash |
| LMArena Text: non-English | 1405 | 1491 | Gemini 3.8 Flash |
| LMArena Text: Chinese | 1427 | 1553 | Gemini 3.8 Flash |
| LMArena Text: German | 1413 | 1501 | Gemini 3.8 Flash |
| LMArena Text: Japanese | 1377 | 1507 | Gemini 3.8 Flash |
| LMArena Text: Korean | 1381 | 1464 | Gemini 3.8 Flash |
| LMArena Text: French | 1433 | 1496 | Gemini 3.8 Flash |
| LMArena Text: Spanish | 1448 | 1487 | Gemini 3.8 Flash |
| LMArena Text: Russian | 1422 | 1514 | Gemini 3.8 Flash |
| LMArena Text: Polish | 1413 | 1497 | Gemini 3.8 Flash |
| LMArena Text: multi-turn | 1444 | 1503 | Gemini 3.8 Flash |
| LMArena Text: longer queries | 1455 | 1507 | Gemini 3.8 Flash |
| LMArena Text: writing and language | 1418 | 1494 | Gemini 3.8 Flash |
| LMArena Text: entertainment and media | 1398 | 1480 | Gemini 3.8 Flash |
| LMArena Vision: English | Not measured | 1318 | Only Gemini 3.8 Flash measured |
| LMArena Vision: Chinese | Not measured | 1416 | Only Gemini 3.8 Flash measured |
| LMArena Vision: reading text | Not measured | 1333 | Only Gemini 3.8 Flash measured |
| LMArena Vision: humor | Not measured | 1321 | Only Gemini 3.8 Flash measured |
| LMArena Vision: creative writing | Not measured | 1299 | Only Gemini 3.8 Flash measured |
| Neither model has a result on the other 12 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.1 | Gemini 3.8 Flash | 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 4.1$0.052Fits in one request
Gemini 3.8 Flash$0.0029Fits in one request
Gemini 3.8 Flash costs less
Repository review
50K input + 3K output tokens
Claude Opus 4.1$0.975Fits in one request
Gemini 3.8 Flash$0.054Fits in one request
Gemini 3.8 Flash costs less
Agent loop
200K input + 10K output tokens
Claude Opus 4.1$3.75Exceeds the context window
Gemini 3.8 Flash$0.206Fits in one request
Gemini 3.8 Flash 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 4.1 | Google Gemini 3.8 Flash |
|---|---|---|
| Maker | Anthropic | |
| Weights | No public weights listed | No public weights listed |
| Released | August 5, 2025 | September 2, 2026 |
| Context window | 200K | 1.05M |
| Input $/Mtok | $15.00 | $0.825 |
| Output $/Mtok | $75.00 | $4.125 |
| Coding index | 27.2 | 70.5 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | Not computable | $2.74 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.1 better than Gemini 3.8 Flash for coding?
Pick Gemini 3.8 Flash for coding: it scores 70.5 on the Vibe Coding Index against 27.2 for Claude Opus 4.1. Claude Opus 4.1 is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Which is cheaper, Claude Opus 4.1 or Gemini 3.8 Flash?
Claude Opus 4.1 costs $15.00 per million input tokens and $75.00 per million output tokens; Gemini 3.8 Flash costs $0.825 and $4.125. Cost per solved task is known for Gemini 3.8 Flash only.
Which has the bigger context window, Claude Opus 4.1 or Gemini 3.8 Flash?
Gemini 3.8 Flash, with 1.05M tokens against 200K.
How many benchmarks is the Claude Opus 4.1 vs Gemini 3.8 Flash comparison based on?
58 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.1's coding index rests on 1 independent benchmark and Gemini 3.8 Flash's on 2. Where only one model has a result, the page says so instead of naming a winner.