Claude Sonnet 5.5 vs GLM 4.5
Claude Sonnet 5.5 leads GLM 4.5 on the Artificial Analysis Intelligence Index, 56.0 to 12.8, and GLM 4.5 costs 4.5x less per output token ($2.20 vs $10.00 per million). Updated October 21, 2026; 34 benchmarks have a result for both.
Claude Sonnet 5.5 or GLM 4.5: which to pick
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; GLM 4.5 has none, so the two cannot be ranked on coding.
Pick GLM 4.5 for output tokens 4.5x cheaper ($2.20 vs $10.00 per million) and work measured by LMArena Text: Spanish, where it leads.
- Shared results
- 34
- Claude Sonnet 5.5 only
- 62
- GLM 4.5 only
- 27
- Like-for-like categories
- 7 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
No call
Only Claude Sonnet 5.5 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 56.0 against 12.8.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only GLM 4.5 has a GPQA Diamond result, 72.2%.
Directional only
Math
AIME
No call
Only GLM 4.5 has a AIME result, 86.7%.
Directional only
Knowledge
MMLU Pro
No call
Only GLM 4.5 has a MMLU Pro result, 81.2%.
Directional only
Web design
Design Arena: websites
Claude Sonnet 5.5
Claude Sonnet 5.5 leads, 1326 against 1170.
Same board, both measured
General
Vals Index
No call
Only Claude Sonnet 5.5 has a Vals Index result, 70.8%.
Directional only
Long documents
Listed context window
Claude Sonnet 5.5
Claude Sonnet 5.5 takes 1M tokens against 131K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GLM 4.5
Claude Sonnet 5.5 $0.0070, GLM 4.5 $0.0017 per turn.
List prices
At a glance
- Coding index
- Claude Sonnet 5.5 87.3 from 5 benchmarks, GLM 4.5 not benchmarked.
- Widest category
- Intelligence, 43.2 points apart on average over 1 shared benchmark.
- Widest single gap
- ALE-Bench: Claude Sonnet 5.5 1819.1 against GLM 4.5 344.8, 49.1 points apart on a 0 to 100 scale.
- Output price
- Claude Sonnet 5.5 $10.00 against GLM 4.5 $2.20 per million output tokens, 4.5x apart.
- Context window
- Claude Sonnet 5.5 takes 1M tokens, GLM 4.5 131K.
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 | GLM 4.5 | Ties |
|---|---|---|---|---|
| Coding | 3 | 0 | ||
| Intelligence | 1 | 0 | ||
| Reasoning | 4 | 0 | ||
| Math | 2 | 0 | ||
| Knowledge | 4 | 0 | ||
| Web design | 6 | 0 | ||
| General | 13 | 1 | ||
| All shared boards | 33 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index30
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| SWE-bench Verified | Not measured | 64.2% | Only GLM 4.5 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 | 67.5% | Only GLM 4.5 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 | 73.8% | Only GLM 4.5 measured |
| SciCode | 61.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 22.0% | Only GLM 4.5 measured |
| FrontierCode | 52.1% | Not measured | Only Claude Sonnet 5.5 measured |
| FrontierSWE | 61.9% | Not measured | Only Claude Sonnet 5.5 measured |
| WeirdML | Not measured | 40.6% | Only GLM 4.5 measured |
| ALE-Bench | 1819.1 | 344.8 | Claude Sonnet 5.5 |
| LMArena Text: coding | 1513 | 1434 | Claude Sonnet 5.5 |
| LMArena Text: software and IT | 1504 | 1440 | Claude Sonnet 5.5 |
| 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 |
| SciCode | 13.8% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 14 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| AA Intelligence Index | 56.0 | 12.8 | Claude Sonnet 5.5 |
| Epoch Capabilities Index | 166.2 | Not measured | Only Claude Sonnet 5.5 measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index19 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1306 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: agents building mobile apps | 1257 | Not measured | Only Claude Sonnet 5.5 measured |
| Design Arena: spreadsheets | 1244 | 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 |
| τ²-Bench Telecom | Not measured | 43.0% | Only GLM 4.5 measured |
| APEX-Agents | 75.5% | Not measured | Only Claude Sonnet 5.5 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 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 72.2% | Only GLM 4.5 measured |
| 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 | 78.2% | Only GLM 4.5 measured |
| Humanity's Last Exam (Artificial Analysis run) | 55.0% | 13.0% | Claude Sonnet 5.5 |
| GPQA Diamond (Epoch AI run) | 95.6% | Not measured | Only Claude Sonnet 5.5 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 |
| LMArena Text: hard prompts | 1494 | 1429 | Claude Sonnet 5.5 |
| LMArena Text: expert | 1531 | 1433 | Claude Sonnet 5.5 |
| LMArena Text: hard prompts in English | 1502 | 1429 | Claude Sonnet 5.5 |
| LMArena Vision: diagrams | 1329 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Vision: homework | 1331 | Not measured | Only Claude Sonnet 5.5 measured |
| Kagi LLM Benchmark | Not measured | 57.9% | Only GLM 4.5 measured |
| Neither model has a result on the other 8 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| AIME | Not measured | 86.7% | Only GLM 4.5 measured |
| MATH 500 (Vals AI) | Not measured | 94.0% | Only GLM 4.5 measured |
| MGSM (Vals AI) | Not measured | 90.8% | Only GLM 4.5 measured |
| AA Math Index | Not measured | 73.7 | Only GLM 4.5 measured |
| AIME 2025 (Artificial Analysis run) | Not measured | 73.7% | Only GLM 4.5 measured |
| 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 | 1427 | Claude Sonnet 5.5 |
| LMArena Text: mathematical work | 1510 | 1430 | Claude Sonnet 5.5 |
| Neither model has a result on the other 2 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 81.2% | Only GLM 4.5 measured |
| LegalBench (Vals AI) | Not measured | 75.6% | Only GLM 4.5 measured |
| CorpFin (Vals AI) | Not measured | 61.0% | Only GLM 4.5 measured |
| TaxEval (Vals AI) | Not measured | 72.4% | Only GLM 4.5 measured |
| MedQA (Vals AI) | Not measured | 90.0% | Only GLM 4.5 measured |
| MedCode (Vals AI) | 52.9% | Not measured | Only Claude Sonnet 5.5 measured |
| MMLU Pro (Artificial Analysis run) | Not measured | 83.5% | Only GLM 4.5 measured |
| SimpleQA Verified | 46.5% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: science | 1483 | 1444 | Claude Sonnet 5.5 |
| LMArena Text: medicine and healthcare | 1464 | 1455 | Claude Sonnet 5.5 |
| LMArena Text: legal and government | 1483 | 1438 | Claude Sonnet 5.5 |
| LMArena Text: business and finance | 1468 | 1420 | Claude Sonnet 5.5 |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | Leader |
|---|---|---|---|
| Design Arena: websites | 1326 | 1170 | Claude Sonnet 5.5 |
| Design Arena: UI components | 1365 | 1144 | Claude Sonnet 5.5 |
| Design Arena: game dev | 1469 | 1145 | Claude Sonnet 5.5 |
| Design Arena: data viz | 1394 | 1159 | Claude Sonnet 5.5 |
| Design Arena: 3D | 1452 | 1170 | Claude Sonnet 5.5 |
| Design Arena: all code categories | 1364 | 1165 | Claude Sonnet 5.5 |
| Design Arena: SVG | Not measured | 1096 | Only GLM 4.5 measured |
| LiveBench design | 85.0% | Not measured | Only Claude Sonnet 5.5 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index131
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | 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 |
| IFBench | Not measured | 44.1% | Only GLM 4.5 measured |
| Long context reasoning (AA-LCR) | 82.7% | 52.7% | Claude Sonnet 5.5 |
| DTBench | 97.3% | Not measured | Only Claude Sonnet 5.5 measured |
| LMCA | 68.3% | Not measured | Only Claude Sonnet 5.5 measured |
| Creative writing (Lech Mazur) | Not measured | 73.4% | Only GLM 4.5 measured |
| Furniture assembly | 75.0% | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text | 1473 | 1430 | Claude Sonnet 5.5 |
| LMArena Text: instruction following | 1492 | 1404 | Claude Sonnet 5.5 |
| LMArena Text: creative writing | 1467 | 1395 | Claude Sonnet 5.5 |
| LMArena Vision | 1287 | Not measured | Only Claude Sonnet 5.5 measured |
| LMArena Text: English | 1484 | 1437 | Claude Sonnet 5.5 |
| LMArena Text: non-English | 1456 | 1417 | Claude Sonnet 5.5 |
| LMArena Text: Chinese | 1535 | 1465 | Claude Sonnet 5.5 |
| LMArena Text: German | Not measured | 1407 | Only GLM 4.5 measured |
| LMArena Text: Japanese | Not measured | 1415 | Only GLM 4.5 measured |
| LMArena Text: Korean | Not measured | 1380 | Only GLM 4.5 measured |
| LMArena Text: French | 1499 | 1418 | Claude Sonnet 5.5 |
| LMArena Text: Spanish | 1451 | 1454 | GLM 4.5 |
| LMArena Text: Russian | 1454 | 1413 | Claude Sonnet 5.5 |
| LMArena Text: Polish | Not measured | 1422 | Only GLM 4.5 measured |
| LMArena Text: multi-turn | 1465 | 1415 | Claude Sonnet 5.5 |
| LMArena Text: longer queries | 1495 | 1412 | Claude Sonnet 5.5 |
| LMArena Text: writing and language | 1474 | 1403 | Claude Sonnet 5.5 |
| LMArena Text: entertainment and media | 1461 | 1404 | Claude Sonnet 5.5 |
| 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 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Sonnet 5.5 | GLM 4.5 | 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 4.5 costs less
Repository review
50K input + 3K output tokens
GLM 4.5 costs less
Agent loop
200K input + 10K output tokens
GLM 4.5 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 | Z.ai GLM 4.5 |
|---|---|---|
| Maker | Anthropic | Z.ai |
| Weights | No public weights listed | Open weights |
| Released | September 28, 2026 | July 25, 2025 |
| Context window | 1M | 131K |
| Input $/Mtok | $2.00 | $0.60 |
| Output $/Mtok | $10.00 | $2.20 |
| Coding index | 87.3 | Not benchmarked |
| Independent measurements behind it | 5 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Sonnet 5.5 better than GLM 4.5 for coding?
Only Claude Sonnet 5.5 has a coding score, 87.3 on the Vibe Coding Index; GLM 4.5 has none, so the two cannot be ranked on coding. Pick GLM 4.5 for output tokens 4.5x cheaper ($2.20 vs $10.00 per million) and work measured by LMArena Text: Spanish, where it leads.
Which is cheaper, Claude Sonnet 5.5 or GLM 4.5?
Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; GLM 4.5 costs $0.60 and $2.20. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Sonnet 5.5 or GLM 4.5?
Claude Sonnet 5.5, with 1M tokens against 131K.
How many benchmarks is the Claude Sonnet 5.5 vs GLM 4.5 comparison based on?
34 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 5 independent benchmarks and GLM 4.5's on 0. Where only one model has a result, the page says so instead of naming a winner.