Claude Opus 4.6 vs GLM 5.3 Flash
Updated October 21, 2026. 73 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick GLM 5.3 Flash for coding: it scores 71.0 on the Vibe Coding Index against 66.9 for Claude Opus 4.6.
Pick Claude Opus 4.6 when what matters is LiveCodeBench (Vals AI) or Vibe Code Bench (Vals AI), where it leads.
- Shared results
- 73
- Claude Opus 4.6 only
- 35
- GLM 5.3 Flash only
- 29
- Like-for-like categories
- 8 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
GLM 5.3 Flash
GLM 5.3 Flash scores 71.0 against 66.9.
2 benchmarks behind each score
Intelligence
AA Intelligence Index
GLM 5.3 Flash
GLM 5.3 Flash leads, 41.8 against 31.9.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GLM 5.3 Flash has a AA Agentic Index result, 50.9.
Directional only
Reasoning
GPQA Diamond
Claude Opus 4.6
Claude Opus 4.6 leads, 89.7% against 86.4%.
Same board, both measured
Math
AIME
No call
Only Claude Opus 4.6 has a AIME result, 95.6%.
Directional only
Knowledge
MMLU Pro
Claude Opus 4.6
Claude Opus 4.6 leads, 89.1% against 86.1%.
Same board, both measured
Web design
Design Arena: websites
Claude Opus 4.6
Claude Opus 4.6 leads, 1291 against 1272.
Same board, both measured
General
Vals Index
No call
Only GLM 5.3 Flash has a Vals Index result, 50.9%.
Directional only
Long documents
Listed context window
GLM 5.3 Flash
GLM 5.3 Flash takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GLM 5.3 Flash
Claude Opus 4.6 $0.018, GLM 5.3 Flash $0.0004 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
GLM 5.3 Flash
Claude Opus 4.6 $1.56, GLM 5.3 Flash $0.02.
Published attempt cost and pass rate
At a glance
- Coding index
- Claude Opus 4.6 66.9 from 2 benchmarks, GLM 5.3 Flash 71.0 from 2 benchmarks.
- Widest category
- Math, 9.5 points apart on average over 6 shared benchmarks.
- Widest single gap
- ProofBench: Claude Opus 4.6 50.0% against GLM 5.3 Flash 21.0%, 29.0 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.6 $25.00 against GLM 5.3 Flash $0.50 per million output tokens, 50.0x apart.
- Context window
- Claude Opus 4.6 takes 1M tokens, GLM 5.3 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 4.6 | Bars | GLM 5.3 Flash | Ties |
|---|---|---|---|---|
| Coding | 4 | 6 | ||
| Intelligence | 1 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 10 | 2 | 2 ties | |
| Math | 6 | 0 | ||
| Knowledge | 7 | 0 | ||
| Web design | 3 | 5 | ||
| General | 23 | 2 | ||
| All shared boards | 54 | 17 | 2 ties |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index46
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| SWE-bench Verified | 75.6% | Not measured | Only Claude Opus 4.6 measured |
| SWE-bench Multilingual | 72.0% | Not measured | Only Claude Opus 4.6 measured |
| LiveBench coding | Not measured | 80.6% | Only GLM 5.3 Flash measured |
| LMArena WebDev | 1547 | 1607 | GLM 5.3 Flash |
| AA Coding Index | Not measured | 71.5 | Only GLM 5.3 Flash measured |
| LiveCodeBench (Vals AI) | 84.7% | 80.5% | Claude Opus 4.6 |
| SWE-bench Verified (Vals AI) | 78.2% | 92.0% | GLM 5.3 Flash |
| Terminal-Bench 4 (Vals AI) | Not measured | 37.4% | Only GLM 5.3 Flash measured |
| Vibe Code Bench (Vals AI) | 57.6% | 30.8% | Claude Opus 4.6 |
| Code migration (Vals AI) | Not measured | 20.5% | Only GLM 5.3 Flash measured |
| ProgramBench (Vals AI) | Not measured | 0.0% | Only GLM 5.3 Flash measured |
| IOI (Vals AI) | Not measured | 52.5% | Only GLM 5.3 Flash measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 62.9% | Only GLM 5.3 Flash measured |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 16.0% | Only GLM 5.3 Flash measured |
| SkillsBench (Vals AI) | Not measured | 40.2% | Only GLM 5.3 Flash measured |
| CyberBench (Vals AI) | Not measured | 67.9% | Only GLM 5.3 Flash measured |
| SciCode | Not measured | 51.6% | Only GLM 5.3 Flash measured |
| Terminal-Bench Hard (Artificial Analysis run) | 48.5% | Not measured | Only Claude Opus 4.6 measured |
| Terminal-Bench | 79.8% | Not measured | Only Claude Opus 4.6 measured |
| FrontierCode | 26.6% | 31.8% | GLM 5.3 Flash |
| FrontierSWE | Not measured | 18.1% | Only GLM 5.3 Flash measured |
| GSO-Bench | 41.2% | Not measured | Only Claude Opus 4.6 measured |
| WeirdML | 78.0% | Not measured | Only Claude Opus 4.6 measured |
| Cybench | 93.0% | Not measured | Only Claude Opus 4.6 measured |
| ALE-Bench | Not measured | 303.6 | Only GLM 5.3 Flash measured |
| LMArena Text: coding | 1534 | 1507 | Claude Opus 4.6 |
| LMArena Text: software and IT | 1527 | 1500 | Claude Opus 4.6 |
| LMArena WebDev: React | 1539 | 1624 | GLM 5.3 Flash |
| LMArena WebDev: HTML | 1559 | 1577 | GLM 5.3 Flash |
| LMArena WebDev: from an image | 1543 | 1578 | GLM 5.3 Flash |
| Neither model has a result on the other 8 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 31.9 | 41.8 | GLM 5.3 Flash |
| Epoch Capabilities Index | 155.7 | 153.1 | Claude Opus 4.6 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 50.9 | Only GLM 5.3 Flash measured |
| Design Arena: agents building web apps | 1206 | Not measured | Only Claude Opus 4.6 measured |
| Design Arena: agents building full-stack apps | 1220 | Not measured | Only Claude Opus 4.6 measured |
| Design Arena: agents building mobile apps | 1207 | Not measured | Only Claude Opus 4.6 measured |
| Design Arena: agents building Android apps | 1204 | Not measured | Only Claude Opus 4.6 measured |
| Design Arena: agents building games | 1214 | Not measured | Only Claude Opus 4.6 measured |
| LiveBench research | Not measured | 70.1% | Only GLM 5.3 Flash measured |
| LiveBench browser | Not measured | 84.0% | Only GLM 5.3 Flash measured |
| LiveBench long agentic | Not measured | 28.4% | Only GLM 5.3 Flash measured |
| SREBench (Vals AI) | Not measured | 0.8% | Only GLM 5.3 Flash measured |
| Finance Agent (Vals AI) | Not measured | 57.9% | Only GLM 5.3 Flash measured |
| Tax Agent Bench (Vals AI) | Not measured | 31.6% | Only GLM 5.3 Flash measured |
| Legal Research Bench (Vals AI) | Not measured | 45.2% | Only GLM 5.3 Flash measured |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 10.4% | Only GLM 5.3 Flash measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 55.9% | Only GLM 5.3 Flash measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 2.9% | Only GLM 5.3 Flash measured |
| τ²-Bench Telecom | 92.1% | Not measured | Only Claude Opus 4.6 measured |
| APEX-Agents | 46.3% | 52.8% | GLM 5.3 Flash |
| METR time horizons | 78.9% | Not measured | Only Claude Opus 4.6 measured |
| Remote Labor Index | 4.2% | Not measured | Only Claude Opus 4.6 measured |
| DeepResearch Bench | 55.3% | Not measured | Only Claude Opus 4.6 measured |
| Vending-Bench 2 | $8,018 | Not measured | Only Claude Opus 4.6 measured |
| Neither model has a result on the other 17 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index102
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| GPQA Diamond | 89.7% | 86.4% | Claude Opus 4.6 |
| LiveBench reasoning | Not measured | 77.6% | Only GLM 5.3 Flash measured |
| MMMU Pro (Vals AI) | 83.9% | 86.0% | GLM 5.3 Flash |
| GPQA Diamond (Artificial Analysis run) | 89.6% | 91.2% | GLM 5.3 Flash |
| Humanity's Last Exam (Artificial Analysis run) | 39.9% | 39.9% | Tie |
| GPQA Diamond (Epoch AI run) | 90.5% | 90.2% | Claude Opus 4.6 |
| ARC-AGI | 94.0% | 91.0% | Claude Opus 4.6 |
| ARC-AGI-2 | 69.2% | 65.8% | Claude Opus 4.6 |
| SimpleBench | 67.6% | Not measured | Only Claude Opus 4.6 measured |
| Chess puzzles | 21.0% | 21.0% | Tie |
| Mystery game puzzles | 25.0% | 8.0% | Claude Opus 4.6 |
| EBR-bench | 12.7% | Not measured | Only Claude Opus 4.6 measured |
| LMArena Text: hard prompts | 1525 | 1490 | Claude Opus 4.6 |
| LMArena Text: expert | 1544 | 1511 | Claude Opus 4.6 |
| LMArena Text: hard prompts in English | 1530 | 1488 | Claude Opus 4.6 |
| LMArena Vision: diagrams | 1340 | 1317 | Claude Opus 4.6 |
| LMArena Vision: homework | 1337 | 1318 | Claude Opus 4.6 |
| Neither model has a result on the other 4 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| AIME | 95.6% | Not measured | Only Claude Opus 4.6 measured |
| OTIS Mock AIME | 94.4% | 93.9% | Claude Opus 4.6 |
| FrontierMath, tiers 1 to 3 | 66.0% | 55.8% | Claude Opus 4.6 |
| FrontierMath, tier 4 | 26.8% | 17.1% | Claude Opus 4.6 |
| ProofBench | 50.0% | 21.0% | Claude Opus 4.6 |
| LMArena Text: math | 1518 | 1503 | Claude Opus 4.6 |
| LMArena Text: mathematical work | 1525 | 1497 | Claude Opus 4.6 |
| Neither model has a result on the other 6 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| MMLU Pro | 89.1% | 86.1% | Claude Opus 4.6 |
| LegalBench (Vals AI) | 85.3% | 83.9% | Claude Opus 4.6 |
| CaseLaw (Vals AI) | 62.1% | Not measured | Only Claude Opus 4.6 measured |
| CorpFin (Vals AI) | 67.0% | Not measured | Only Claude Opus 4.6 measured |
| TaxEval (Vals AI) | 76.0% | 75.6% | Claude Opus 4.6 |
| MortgageTax (Vals AI) | 68.5% | Not measured | Only Claude Opus 4.6 measured |
| MedQA (Vals AI) | 95.4% | Not measured | Only Claude Opus 4.6 measured |
| MedCode (Vals AI) | 49.1% | Not measured | Only Claude Opus 4.6 measured |
| SimpleQA Verified | 47.0% | Not measured | Only Claude Opus 4.6 measured |
| LMArena Text: science | 1519 | 1484 | Claude Opus 4.6 |
| LMArena Text: medicine and healthcare | 1504 | 1475 | Claude Opus 4.6 |
| LMArena Text: legal and government | 1512 | 1473 | Claude Opus 4.6 |
| LMArena Text: business and finance | 1497 | 1460 | Claude Opus 4.6 |
| Neither model has a result on the other 4 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index35
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| Design Arena: websites | 1291 | 1272 | Claude Opus 4.6 |
| Design Arena: UI components | 1284 | 1316 | GLM 5.3 Flash |
| Design Arena: game dev | 1278 | 1279 | GLM 5.3 Flash |
| Design Arena: data viz | 1279 | 1262 | Claude Opus 4.6 |
| Design Arena: 3D | 1274 | 1316 | GLM 5.3 Flash |
| Design Arena: all code categories | 1289 | 1282 | Claude Opus 4.6 |
| Design Arena: SVG | 1227 | 1284 | GLM 5.3 Flash |
| Design Arena: ASCII art | 1254 | 1269 | GLM 5.3 Flash |
| LiveBench design | Not measured | 77.2% | Only GLM 5.3 Flash measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index232
| Benchmark | Claude Opus 4.6 | GLM 5.3 Flash | Leader |
|---|---|---|---|
| Vals Index | Not measured | 50.9% | Only GLM 5.3 Flash measured |
| LiveBench data analysis | Not measured | 76.4% | Only GLM 5.3 Flash measured |
| SAGE (Vals AI) | 51.6% | Not measured | Only Claude Opus 4.6 measured |
| MedScribe (Vals AI) | 86.7% | 88.9% | GLM 5.3 Flash |
| IFBench | 53.1% | Not measured | Only Claude Opus 4.6 measured |
| Long context reasoning (AA-LCR) | 78.0% | 80.0% | GLM 5.3 Flash |
| DTBench | 91.2% | Not measured | Only Claude Opus 4.6 measured |
| LMCA | 55.8% | Not measured | Only Claude Opus 4.6 measured |
| CL-bench | 20.7% | Not measured | Only Claude Opus 4.6 measured |
| Surface Evolver Bench | Not measured | 52.5% | Only GLM 5.3 Flash measured |
| Furniture assembly | 28.3% | Not measured | Only Claude Opus 4.6 measured |
| CL-bench Life | 17.0% | Not measured | Only Claude Opus 4.6 measured |
| LMArena Text | 1501 | 1471 | Claude Opus 4.6 |
| LMArena Text: instruction following | 1521 | 1478 | Claude Opus 4.6 |
| LMArena Text: creative writing | 1505 | 1441 | Claude Opus 4.6 |
| LMArena Vision | 1316 | 1294 | Claude Opus 4.6 |
| LMArena Text: English | 1511 | 1474 | Claude Opus 4.6 |
| LMArena Text: non-English | 1488 | 1462 | Claude Opus 4.6 |
| LMArena Text: Chinese | 1551 | 1531 | Claude Opus 4.6 |
| LMArena Text: German | 1500 | 1462 | Claude Opus 4.6 |
| LMArena Text: Japanese | 1488 | 1444 | Claude Opus 4.6 |
| LMArena Text: Korean | 1464 | 1436 | Claude Opus 4.6 |
| LMArena Text: French | 1512 | 1491 | Claude Opus 4.6 |
| LMArena Text: Spanish | 1510 | 1475 | Claude Opus 4.6 |
| LMArena Text: Russian | 1497 | 1465 | Claude Opus 4.6 |
| LMArena Text: Polish | 1499 | 1450 | Claude Opus 4.6 |
| LMArena Text: multi-turn | 1511 | 1469 | Claude Opus 4.6 |
| LMArena Text: longer queries | 1518 | 1481 | Claude Opus 4.6 |
| LMArena Text: writing and language | 1502 | 1455 | Claude Opus 4.6 |
| LMArena Text: entertainment and media | 1492 | 1440 | Claude Opus 4.6 |
| LMArena Vision: English | 1324 | 1295 | Claude Opus 4.6 |
| LMArena Vision: Chinese | 1370 | 1363 | Claude Opus 4.6 |
| LMArena Vision: reading text | 1326 | 1299 | Claude Opus 4.6 |
| LMArena Vision: humor | 1314 | 1279 | Claude Opus 4.6 |
| LMArena Vision: recognizing things | 1274 | Not measured | Only Claude Opus 4.6 measured |
| LMArena Vision: creative writing | 1331 | 1270 | Claude Opus 4.6 |
| LMArena Document | 1507 | Not measured | Only Claude Opus 4.6 measured |
| Neither model has a result on the other 9 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.6 | GLM 5.3 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
GLM 5.3 Flash costs less
Repository review
50K input + 3K output tokens
GLM 5.3 Flash costs less
Agent loop
200K input + 10K output tokens
GLM 5.3 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 4.6 | Z.ai GLM 5.3 Flash |
|---|---|---|
| Maker | Anthropic | Z.ai |
| Weights | No public weights listed | Open weights |
| Released | February 4, 2026 | August 26, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $5.00 | $0.15 |
| Output $/Mtok | $25.00 | $0.50 |
| Coding index | 66.9 | 71.0 |
| Independent measurements behind it | 2 | 2 |
| Cost per solved task | $1.56 | $0.02 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.6 better than GLM 5.3 Flash for coding?
Pick GLM 5.3 Flash for coding: it scores 71.0 on the Vibe Coding Index against 66.9 for Claude Opus 4.6. Pick Claude Opus 4.6 when what matters is LiveCodeBench (Vals AI) or Vibe Code Bench (Vals AI), where it leads.
Which is cheaper, Claude Opus 4.6 or GLM 5.3 Flash?
Claude Opus 4.6 costs $5.00 per million input tokens and $25.00 per million output tokens; GLM 5.3 Flash costs $0.15 and $0.50. Per solved SWE-bench Verified task, Claude Opus 4.6 costs $1.56 and GLM 5.3 Flash $0.02.
Which has the bigger context window, Claude Opus 4.6 or GLM 5.3 Flash?
GLM 5.3 Flash, with 1.05M tokens against 1M.
How many benchmarks is the Claude Opus 4.6 vs GLM 5.3 Flash comparison based on?
73 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.6's coding index rests on 2 independent benchmarks and GLM 5.3 Flash's on 2. Where only one model has a result, the page says so instead of naming a winner.