Claude Fable 5.2 vs GLM 5.3
Claude Fable 5.2 leads GLM 5.3 on coding, 87.8 to 68.5 on the Vibe Coding Index, and GLM 5.3 costs 9.1x less per output token ($4.40 vs $40.00 per million). Updated November 14, 2026; 46 benchmarks have a result for both.
Claude Fable 5.2 or GLM 5.3: which to pick
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 68.5 for GLM 5.3, though on 4 benchmarks against 5.
Pick GLM 5.3 for output tokens 9.1x cheaper ($4.40 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
- Shared results
- 46
- Claude Fable 5.2 only
- 22
- GLM 5.3 only
- 63
- 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 Fable 5.2
Claude Fable 5.2 scores 87.8 against 68.5.
4 and 5 benchmarks behind the scores
Intelligence
AA Intelligence Index
Claude Fable 5.2
Claude Fable 5.2 leads, 64.6 against 31.7.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GLM 5.3 has a AA Agentic Index result, 53.1.
Directional only
Reasoning
GPQA Diamond
No call
Only GLM 5.3 has a GPQA Diamond result, 88.1%.
Directional only
Knowledge
MMLU Pro
No call
Only GLM 5.3 has a MMLU Pro result, 86.8%.
Directional only
Web design
Design Arena: websites
Claude Fable 5.2
Claude Fable 5.2 leads, 1351 against 1279.
Same board, both measured
General
Vals Index
Claude Fable 5.2
Claude Fable 5.2 leads, 71.3% against 59.9%.
Same board, both measured
Long documents
Listed context window
GLM 5.3
GLM 5.3 takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GLM 5.3
Claude Fable 5.2 $0.028, GLM 5.3 $0.0036 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GLM 5.3 has the number, $0.36.
Directional only
At a glance
- Coding index
- Claude Fable 5.2 87.8 from 4 benchmarks, GLM 5.3 68.5 from 5 benchmarks.
- Widest category
- Knowledge, 41.7 points apart on average over 2 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: Claude Fable 5.2 100.0% against GLM 5.3 29.3%, 70.7 points apart on a 0 to 100 scale.
- Output price
- Claude Fable 5.2 $40.00 against GLM 5.3 $4.40 per million output tokens, 9.1x apart.
- Context window
- Claude Fable 5.2 takes 1M tokens, GLM 5.3 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 Fable 5.2 | Bars | GLM 5.3 | Ties |
|---|---|---|---|---|
| Coding | 13 | 0 | ||
| Intelligence | 2 | 0 | ||
| Agentic work | 3 | 3 | ||
| Reasoning | 9 | 0 | ||
| Math | 4 | 0 | ||
| Knowledge | 2 | 0 | ||
| Web design | 5 | 0 | ||
| General | 5 | 0 | ||
| All shared boards | 43 | 3 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index130
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| LiveBench coding | 79.2% | Not measured | Only Claude Fable 5.2 measured |
| LMArena WebDev | 1838 | 1622 | Claude Fable 5.2 |
| AA Coding Index | Not measured | 74.8 | Only GLM 5.3 measured |
| LiveCodeBench (Vals AI) | Not measured | 80.5% | Only GLM 5.3 measured |
| SWE-bench Verified (Vals AI) | Not measured | 95.4% | Only GLM 5.3 measured |
| Terminal-Bench 4 (Vals AI) | 65.2% | 38.9% | Claude Fable 5.2 |
| Vibe Code Bench (Vals AI) | 93.8% | 78.1% | Claude Fable 5.2 |
| Code migration (Vals AI) | Not measured | 44.2% | Only GLM 5.3 measured |
| ProgramBench (Vals AI) | 19.0% | 1.5% | Claude Fable 5.2 |
| IOI (Vals AI) | Not measured | 68.4% | Only GLM 5.3 measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 71.5% | Only GLM 5.3 measured |
| SWE-bench Multimodal (Vals AI) | 62.3% | Not measured | Only Claude Fable 5.2 measured |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 20.0% | Only GLM 5.3 measured |
| SkillsBench (Vals AI) | Not measured | 47.5% | Only GLM 5.3 measured |
| CyberBench (Vals AI) | Not measured | 72.1% | Only GLM 5.3 measured |
| SciCode | 67.7% | 59.0% | Claude Fable 5.2 |
| Terminal-Bench 4.0 (Artificial Analysis run) | 61.6% | 41.9% | Claude Fable 5.2 |
| FrontierCode 2.0 | 49.1% | 21.6% | Claude Fable 5.2 |
| FrontierCode | Not measured | 40.1% | Only GLM 5.3 measured |
| FrontierSWE | 69.9% | 30.2% | Claude Fable 5.2 |
| WeirdML | Not measured | 75.4% | Only GLM 5.3 measured |
| ALE-Bench | 2509.8 | 1317.4 | Claude Fable 5.2 |
| LMArena Text: coding | Not measured | 1499 | Only GLM 5.3 measured |
| LMArena Text: software and IT | Not measured | 1495 | Only GLM 5.3 measured |
| LMArena WebDev: React | 1915 | 1642 | Claude Fable 5.2 |
| LMArena WebDev: HTML | 1738 | 1596 | Claude Fable 5.2 |
| SWE-Bench Pro V2 | Not measured | 95.6% | Only GLM 5.3 measured |
| GameBench 2 | 99.1 | 72.3 | Claude Fable 5.2 |
| Terminal-Bench 3.0 | Not measured | 32.4% | Only GLM 5.3 measured |
| Terminal-Bench 4.0 | Not measured | 41.8% | Only GLM 5.3 measured |
| CursorBench 4.0 | 60.0% | 42.6% | Claude Fable 5.2 |
| Neither model has a result on the other 21 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| AA Intelligence Index | 64.6 | 31.7 | Claude Fable 5.2 |
| Epoch Capabilities Index | 173.4 | 157.1 | Claude Fable 5.2 |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index33
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 53.1 | Only GLM 5.3 measured |
| Design Arena: agents building web apps | Not measured | 1270 | Only GLM 5.3 measured |
| Design Arena: agents building full-stack apps | 1402 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: agents building mobile apps | 1325 | 1184 | Claude Fable 5.2 |
| Design Arena: HTML slides | Not measured | 1189 | Only GLM 5.3 measured |
| Design Arena: PowerPoint slides | Not measured | 1217 | Only GLM 5.3 measured |
| Design Arena: spreadsheets | 1434 | Not measured | Only Claude Fable 5.2 measured |
| LiveBench research | 94.5% | Not measured | Only Claude Fable 5.2 measured |
| LiveBench browser | 86.9% | Not measured | Only Claude Fable 5.2 measured |
| LiveBench long agentic | 82.9% | Not measured | Only Claude Fable 5.2 measured |
| SREBench (Vals AI) | Not measured | 9.2% | Only GLM 5.3 measured |
| Finance Agent (Vals AI) | Not measured | 55.8% | Only GLM 5.3 measured |
| Tax Agent Bench (Vals AI) | 32.1% | 43.3% | GLM 5.3 |
| Legal Research Bench (Vals AI) | 46.1% | 49.0% | GLM 5.3 |
| Harvey's Legal Agent Benchmark (Vals AI) | 5.0% | 14.6% | GLM 5.3 |
| Excel Modeling Benchmark (Vals AI) | Not measured | 56.3% | Only GLM 5.3 measured |
| BioMysteryBench (Vals AI) | 83.7% | Not measured | Only Claude Fable 5.2 measured |
| Terminal-Bench-Science (Vals AI) | 55.7% | 5.7% | Claude Fable 5.2 |
| Vals Science Index | 63.7% | Not measured | Only Claude Fable 5.2 measured |
| APEX-Agents | 80.1% | 56.6% | Claude Fable 5.2 |
| Remote Labor Index | 41.3% | Not measured | Only Claude Fable 5.2 measured |
| PostTrainBench | Not measured | 34.5% | Only GLM 5.3 measured |
| SpireClimb | 15.5% | Not measured | Only Claude Fable 5.2 measured |
| Vending-Bench 2 | Not measured | $8,164 | Only GLM 5.3 measured |
| MCP Atlas | Not measured | 84.2% | Only GLM 5.3 measured |
| Neither model has a result on the other 19 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index90
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 88.1% | Only GLM 5.3 measured |
| LiveBench reasoning | 88.8% | Not measured | Only Claude Fable 5.2 measured |
| MysteryMechanism (Vals AI) | 51.8% | 23.0% | Claude Fable 5.2 |
| GPQA Diamond (Artificial Analysis run) | Not measured | 91.7% | Only GLM 5.3 measured |
| Humanity's Last Exam (Artificial Analysis run) | 74.3% | 42.3% | Claude Fable 5.2 |
| HLE-Diamond (Artificial Analysis run) | 80.2% | 17.9% | Claude Fable 5.2 |
| CritPt v2, hard subset (Artificial Analysis run) | 76.5% | 33.5% | Claude Fable 5.2 |
| GPQA Diamond (Epoch AI run) | 93.9% | 90.9% | Claude Fable 5.2 |
| ARC-AGI | 98.5% | Not measured | Only Claude Fable 5.2 measured |
| ARC-AGI-2 | 93.8% | Not measured | Only Claude Fable 5.2 measured |
| SimpleBench | 94.9% | 66.2% | Claude Fable 5.2 |
| Chess puzzles | 79.0% | 37.0% | Claude Fable 5.2 |
| Mystery game puzzles | 90.0% | 33.0% | Claude Fable 5.2 |
| EBR-bench | 90.5% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: hard prompts | Not measured | 1493 | Only GLM 5.3 measured |
| LMArena Text: expert | Not measured | 1519 | Only GLM 5.3 measured |
| LMArena Text: hard prompts in English | Not measured | 1500 | Only GLM 5.3 measured |
| Humanity's Last Exam (Scale run) | 72.4% | 16.4% | Claude Fable 5.2 |
| GoBench | 2566 | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 7 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 99.7% | 91.1% | Claude Fable 5.2 |
| FrontierMath, tiers 1 to 3 | 95.1% | 68.8% | Claude Fable 5.2 |
| FrontierMath, tier 4 | 100.0% | 29.3% | Claude Fable 5.2 |
| ProofBench | 100.0% | 49.0% | Claude Fable 5.2 |
| LMArena Text: math | Not measured | 1500 | Only GLM 5.3 measured |
| LMArena Text: mathematical work | Not measured | 1502 | Only GLM 5.3 measured |
| MathArena | 82.8% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 86.8% | Only GLM 5.3 measured |
| LegalBench (Vals AI) | Not measured | 84.8% | Only GLM 5.3 measured |
| TaxEval (Vals AI) | Not measured | 72.4% | Only GLM 5.3 measured |
| MedCode (Vals AI) | Not measured | 42.9% | Only GLM 5.3 measured |
| AA-Omniscience | 66.8 | 6.0 | Claude Fable 5.2 |
| SimpleQA Verified | 94.0% | 41.0% | Claude Fable 5.2 |
| LMArena Text: science | Not measured | 1499 | Only GLM 5.3 measured |
| LMArena Text: medicine and healthcare | Not measured | 1483 | Only GLM 5.3 measured |
| LMArena Text: legal and government | Not measured | 1481 | Only GLM 5.3 measured |
| LMArena Text: business and finance | Not measured | 1461 | Only GLM 5.3 measured |
| PRBench Finance | 47.1% | Not measured | Only Claude Fable 5.2 measured |
| PRBench Legal | 49.0% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 9 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| Design Arena: websites | 1351 | 1279 | Claude Fable 5.2 |
| Design Arena: UI components | 1371 | 1284 | Claude Fable 5.2 |
| Design Arena: game dev | 1396 | 1289 | Claude Fable 5.2 |
| Design Arena: data viz | Not measured | 1251 | Only GLM 5.3 measured |
| Design Arena: 3D | 1517 | 1295 | Claude Fable 5.2 |
| Design Arena: all code categories | 1373 | 1284 | Claude Fable 5.2 |
| Design Arena: SVG | Not measured | 1246 | Only GLM 5.3 measured |
| Design Arena: ASCII art | Not measured | 1208 | Only GLM 5.3 measured |
| LiveBench design | 85.1% | Not measured | Only Claude Fable 5.2 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Fable 5.2 | GLM 5.3 | Leader |
|---|---|---|---|
| Vals Index | 71.3% | 59.9% | Claude Fable 5.2 |
| LiveBench data analysis | 81.5% | Not measured | Only Claude Fable 5.2 measured |
| Public Benefits Bench (Vals AI) | Not measured | 68.5% | Only GLM 5.3 measured |
| MedScribe (Vals AI) | Not measured | 88.8% | Only GLM 5.3 measured |
| Long context reasoning (AA-LCR) | 83.3% | 79.7% | Claude Fable 5.2 |
| GDPval-AA | 1831 | 1655 | Claude Fable 5.2 |
| DTBench | 99.2% | 87.7% | Claude Fable 5.2 |
| LMCA | 70.6% | 55.5% | Claude Fable 5.2 |
| Furniture assembly | 90.0% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text | Not measured | 1475 | Only GLM 5.3 measured |
| LMArena Text: instruction following | Not measured | 1483 | Only GLM 5.3 measured |
| LMArena Text: creative writing | Not measured | 1459 | Only GLM 5.3 measured |
| LMArena Text: English | Not measured | 1483 | Only GLM 5.3 measured |
| LMArena Text: non-English | Not measured | 1462 | Only GLM 5.3 measured |
| LMArena Text: Chinese | Not measured | 1535 | Only GLM 5.3 measured |
| LMArena Text: German | Not measured | 1497 | Only GLM 5.3 measured |
| LMArena Text: Japanese | Not measured | 1470 | Only GLM 5.3 measured |
| LMArena Text: Korean | Not measured | 1440 | Only GLM 5.3 measured |
| LMArena Text: French | Not measured | 1498 | Only GLM 5.3 measured |
| LMArena Text: Spanish | Not measured | 1467 | Only GLM 5.3 measured |
| LMArena Text: Russian | Not measured | 1472 | Only GLM 5.3 measured |
| LMArena Text: Polish | Not measured | 1463 | Only GLM 5.3 measured |
| LMArena Text: multi-turn | Not measured | 1474 | Only GLM 5.3 measured |
| LMArena Text: longer queries | Not measured | 1486 | Only GLM 5.3 measured |
| LMArena Text: writing and language | Not measured | 1468 | Only GLM 5.3 measured |
| LMArena Text: entertainment and media | Not measured | 1447 | Only GLM 5.3 measured |
| Neither model has a result on the other 23 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Fable 5.2 | GLM 5.3 | 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 costs less
Repository review
50K input + 3K output tokens
GLM 5.3 costs less
Agent loop
200K input + 10K output tokens
GLM 5.3 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 Fable 5.2 | Z.ai GLM 5.3 |
|---|---|---|
| Maker | Anthropic | Z.ai |
| Weights | No public weights listed | Open weights |
| Released | November 9, 2026 | August 18, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $8.00 | $1.40 |
| Output $/Mtok | $40.00 | $4.40 |
| Coding index | 87.8 | 68.5 |
| Independent measurements behind it | 4 | 5 |
| Cost per solved task | Not computable | $0.36 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Fable 5.2 better than GLM 5.3 for coding?
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 68.5 for GLM 5.3, though on 4 benchmarks against 5. Pick GLM 5.3 for output tokens 9.1x cheaper ($4.40 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
Which is cheaper, Claude Fable 5.2 or GLM 5.3?
Claude Fable 5.2 costs $8.00 per million input tokens and $40.00 per million output tokens; GLM 5.3 costs $1.40 and $4.40. Cost per solved task is known for GLM 5.3 only.
Which has the bigger context window, Claude Fable 5.2 or GLM 5.3?
GLM 5.3, with 1.05M tokens against 1M.
How many benchmarks is the Claude Fable 5.2 vs GLM 5.3 comparison based on?
46 benchmarks have a result for both models as of November 14, 2026. Claude Fable 5.2's coding index rests on 4 independent benchmarks and GLM 5.3's on 5. Where only one model has a result, the page says so instead of naming a winner.