GLM 4.5 Air vs GPT-5.6 Terra
GPT-5.6 Terra leads GLM 4.5 Air on the Artificial Analysis Intelligence Index, 42.1 to 11.1, and GLM 4.5 Air costs 10.9x less per output token ($1.10 vs $12.00 per million). Updated October 22, 2026; 43 benchmarks have a result for both.
vs boards won of 43 shared
GLM 4.5 Air or GPT-5.6 Terra: which to pick
Only GPT-5.6 Terra has a coding score, 63.9 on the Vibe Coding Index; GLM 4.5 Air has none, so the two cannot be ranked on coding.
Pick GLM 4.5 Air for output tokens 10.9x cheaper ($1.10 vs $12.00 per million).
Model AGLM 4.5 AirZ.aiNot benchmarkedNo coding benchmarkNo cost per solved taskModel BGPT-5.6 TerraOpenAI63.9/1006 independent benchmarks$0.42 per solved task
- Shared results
- 43
- GLM 4.5 Air only
- 6
- GPT-5.6 Terra only
- 86
- 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
No call
Only GPT-5.6 Terra has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
GPT-5.6 Terra
GPT-5.6 Terra leads, 42.1 against 11.1.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GPT-5.6 Terra has a AA Agentic Index result, 43.2.
Directional only
Reasoning
GPQA Diamond
No call
Only GPT-5.6 Terra has a GPQA Diamond result, 90.9%.
Directional only
Knowledge
MMLU Pro
No call
Only GPT-5.6 Terra has a MMLU Pro result, 86.7%.
Directional only
Web design
Design Arena: websites
GPT-5.6 Terra
GPT-5.6 Terra leads, 1268 against 1146.
Same board, both measured
Long documents
Listed context window
GPT-5.6 Terra
GPT-5.6 Terra takes 1.05M tokens against 131K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GLM 4.5 Air
GLM 4.5 Air $0.0008, GPT-5.6 Terra $0.0080 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GPT-5.6 Terra has the number, $0.42.
Directional only
At a glance
- Coding index
- GLM 4.5 Air not benchmarked, GPT-5.6 Terra 63.9 from 6 benchmarks.
- Widest category
- Agentic work, 39.8 points apart on average over 1 shared benchmark.
- Widest single gap
- Terminal-Bench Hard (Artificial Analysis run): GLM 4.5 Air 20.5% against GPT-5.6 Terra 62.9%, 42.4 points apart on a 0 to 100 scale.
- Output price
- GLM 4.5 Air $1.10 against GPT-5.6 Terra $12.00 per million output tokens, 10.9x apart.
- Context window
- GLM 4.5 Air takes 131K tokens, GPT-5.6 Terra 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 | GLM 4.5 Air | Bars | GPT-5.6 Terra | Ties |
|---|---|---|---|---|
| Coding | 0 | 3 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 6 | ||
| Math | 0 | 2 | ||
| Knowledge | 0 | 4 | ||
| Web design | 0 | 7 | ||
| General | 0 | 19 | ||
| All shared boards | 0 | 43 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index03
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 86.2% | Only GPT-5.6 Terra measured |
| LMArena WebDev | Not measured | 1522 | Only GPT-5.6 Terra measured |
| AA Coding Index | Not measured | 76.7 | Only GPT-5.6 Terra measured |
| LiveCodeBench (Vals AI) | Not measured | 85.9% | Only GPT-5.6 Terra measured |
| SWE-bench Verified (Vals AI) | Not measured | 95.4% | Only GPT-5.6 Terra measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 22.7% | Only GPT-5.6 Terra measured |
| Vibe Code Bench (Vals AI) | Not measured | 74.6% | Only GPT-5.6 Terra measured |
| Code migration (Vals AI) | Not measured | 47.8% | Only GPT-5.6 Terra measured |
| ProgramBench (Vals AI) | Not measured | 0.5% | Only GPT-5.6 Terra measured |
| IOI (Vals AI) | Not measured | 87.6% | Only GPT-5.6 Terra measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 77.5% | Only GPT-5.6 Terra measured |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 14.8% | Only GPT-5.6 Terra measured |
| SkillsBench (Vals AI) | Not measured | 58.9% | Only GPT-5.6 Terra measured |
| CyberBench (Vals AI) | Not measured | 72.1% | Only GPT-5.6 Terra measured |
| LiveCodeBench (Artificial Analysis run) | 68.4% | Not measured | Only GLM 4.5 Air measured |
| SciCode | Not measured | 55.0% | Only GPT-5.6 Terra measured |
| Terminal-Bench Hard (Artificial Analysis run) | 20.5% | 62.9% | GPT-5.6 Terra |
| FrontierCode | Not measured | 41.3% | Only GPT-5.6 Terra measured |
| GSO-Bench | 2.9% | Not measured | Only GLM 4.5 Air measured |
| WeirdML | Not measured | 78.3% | Only GPT-5.6 Terra measured |
| ALE-Bench | Not measured | 1951.4 | Only GPT-5.6 Terra measured |
| LMArena Text: coding | 1397 | 1485 | GPT-5.6 Terra |
| LMArena Text: software and IT | 1401 | 1482 | GPT-5.6 Terra |
| LMArena WebDev: React | Not measured | 1513 | Only GPT-5.6 Terra measured |
| LMArena WebDev: HTML | Not measured | 1526 | Only GPT-5.6 Terra measured |
| LMArena WebDev: from an image | Not measured | 1541 | Only GPT-5.6 Terra measured |
| SciCode | Not measured | 10.8% | Only GPT-5.6 Terra measured |
| SWE-Bench Pro V2 | Not measured | 92.4% | Only GPT-5.6 Terra measured |
| Neither model has a result on the other 15 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| AA Intelligence Index | 11.1 | 42.1 | GPT-5.6 Terra |
| Epoch Capabilities Index | Not measured | 160.1 | Only GPT-5.6 Terra measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 43.2 | Only GPT-5.6 Terra measured |
| Design Arena: agents building web apps | Not measured | 1120 | Only GPT-5.6 Terra measured |
| Design Arena: agents building full-stack apps | Not measured | 1061 | Only GPT-5.6 Terra measured |
| Design Arena: agents building mobile apps | Not measured | 1110 | Only GPT-5.6 Terra measured |
| Design Arena: agents building Android apps | Not measured | 1060 | Only GPT-5.6 Terra measured |
| Design Arena: agents building games | Not measured | 1083 | Only GPT-5.6 Terra measured |
| Design Arena: HTML slides | Not measured | 1047 | Only GPT-5.6 Terra measured |
| Design Arena: PowerPoint slides | Not measured | 1104 | Only GPT-5.6 Terra measured |
| LiveBench research | Not measured | 60.4% | Only GPT-5.6 Terra measured |
| LiveBench browser | Not measured | 84.0% | Only GPT-5.6 Terra measured |
| LiveBench long agentic | Not measured | 48.4% | Only GPT-5.6 Terra measured |
| SREBench (Vals AI) | Not measured | 9.5% | Only GPT-5.6 Terra measured |
| Finance Agent (Vals AI) | Not measured | 54.4% | Only GPT-5.6 Terra measured |
| Tax Agent Bench (Vals AI) | Not measured | 30.0% | Only GPT-5.6 Terra measured |
| Legal Research Bench (Vals AI) | Not measured | 41.4% | Only GPT-5.6 Terra measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 66.2% | Only GPT-5.6 Terra measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 10.0% | Only GPT-5.6 Terra measured |
| τ²-Bench Telecom | 46.5% | 86.3% | GPT-5.6 Terra |
| APEX-Agents | Not measured | 58.2% | Only GPT-5.6 Terra measured |
| BALROG | Not measured | 53.2% | Only GPT-5.6 Terra measured |
| Vending-Bench 2 | Not measured | $7,343 | Only GPT-5.6 Terra measured |
| Neither model has a result on the other 21 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 90.9% | Only GPT-5.6 Terra measured |
| LiveBench reasoning | Not measured | 90.6% | Only GPT-5.6 Terra measured |
| MMMU Pro (Vals AI) | Not measured | 86.5% | Only GPT-5.6 Terra measured |
| GPQA Diamond (Artificial Analysis run) | 73.3% | 92.5% | GPT-5.6 Terra |
| Humanity's Last Exam (Artificial Analysis run) | 7.0% | 42.9% | GPT-5.6 Terra |
| GPQA Diamond (Epoch AI run) | Not measured | 93.3% | Only GPT-5.6 Terra measured |
| ARC-AGI | Not measured | 96.5% | Only GPT-5.6 Terra measured |
| ARC-AGI-2 | Not measured | 83.9% | Only GPT-5.6 Terra measured |
| SimpleBench | Not measured | 48.9% | Only GPT-5.6 Terra measured |
| Chess puzzles | Not measured | 47.0% | Only GPT-5.6 Terra measured |
| Mystery game puzzles | Not measured | 35.0% | Only GPT-5.6 Terra measured |
| LMArena Text: hard prompts | 1379 | 1469 | GPT-5.6 Terra |
| LMArena Text: expert | 1370 | 1496 | GPT-5.6 Terra |
| LMArena Text: hard prompts in English | 1388 | 1465 | GPT-5.6 Terra |
| LMArena Vision: diagrams | Not measured | 1295 | Only GPT-5.6 Terra measured |
| LMArena Vision: homework | Not measured | 1312 | Only GPT-5.6 Terra measured |
| Kagi LLM Benchmark | 43.0% | 51.3% | GPT-5.6 Terra |
| Neither model has a result on the other 6 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| AA Math Index | 80.7 | Not measured | Only GLM 4.5 Air measured |
| AIME 2025 (Artificial Analysis run) | 80.7% | Not measured | Only GLM 4.5 Air measured |
| OTIS Mock AIME | Not measured | 99.7% | Only GPT-5.6 Terra measured |
| FrontierMath, tiers 1 to 3 | Not measured | 86.0% | Only GPT-5.6 Terra measured |
| FrontierMath, tier 4 | Not measured | 70.7% | Only GPT-5.6 Terra measured |
| ProofBench | Not measured | 74.0% | Only GPT-5.6 Terra measured |
| LMArena Text: math | 1396 | 1465 | GPT-5.6 Terra |
| LMArena Text: mathematical work | 1396 | 1478 | GPT-5.6 Terra |
| MathArena | 12.0% | Not measured | Only GLM 4.5 Air measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 86.7% | Only GPT-5.6 Terra measured |
| LegalBench (Vals AI) | Not measured | 85.1% | Only GPT-5.6 Terra measured |
| CorpFin (Vals AI) | Not measured | 65.3% | Only GPT-5.6 Terra measured |
| TaxEval (Vals AI) | Not measured | 76.2% | Only GPT-5.6 Terra measured |
| MortgageTax (Vals AI) | Not measured | 67.3% | Only GPT-5.6 Terra measured |
| MedCode (Vals AI) | Not measured | 43.4% | Only GPT-5.6 Terra measured |
| MMLU Pro (Artificial Analysis run) | 81.5% | Not measured | Only GLM 4.5 Air measured |
| SimpleQA Verified | Not measured | 43.2% | Only GPT-5.6 Terra measured |
| LMArena Text: science | 1407 | 1452 | GPT-5.6 Terra |
| LMArena Text: medicine and healthcare | 1402 | 1430 | GPT-5.6 Terra |
| LMArena Text: legal and government | 1382 | 1461 | GPT-5.6 Terra |
| LMArena Text: business and finance | 1371 | 1448 | GPT-5.6 Terra |
| FACTS Benchmark Suite | Not measured | 52.0% | Only GPT-5.6 Terra measured |
| Neither model has a result on the other 7 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index07
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| Design Arena: websites | 1146 | 1268 | GPT-5.6 Terra |
| Design Arena: UI components | 1121 | 1256 | GPT-5.6 Terra |
| Design Arena: game dev | 1093 | 1229 | GPT-5.6 Terra |
| Design Arena: data viz | 1186 | 1240 | GPT-5.6 Terra |
| Design Arena: 3D | 1122 | 1134 | GPT-5.6 Terra |
| Design Arena: all code categories | 1137 | 1240 | GPT-5.6 Terra |
| Design Arena: SVG | 1070 | 1219 | GPT-5.6 Terra |
| Design Arena: ASCII art | Not measured | 1178 | Only GPT-5.6 Terra measured |
| LiveBench design | Not measured | 76.0% | Only GPT-5.6 Terra measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index019
| Benchmark | GLM 4.5 Air | GPT-5.6 Terra | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 79.3% | Only GPT-5.6 Terra measured |
| Public Benefits Bench (Vals AI) | Not measured | 62.4% | Only GPT-5.6 Terra measured |
| SAGE (Vals AI) | Not measured | 47.0% | Only GPT-5.6 Terra measured |
| MedScribe (Vals AI) | Not measured | 82.9% | Only GPT-5.6 Terra measured |
| Vals Multimodal Index | Not measured | 65.1% | Only GPT-5.6 Terra measured |
| IFBench | 37.6% | 71.2% | GPT-5.6 Terra |
| Long context reasoning (AA-LCR) | 46.7% | 83.0% | GPT-5.6 Terra |
| DTBench | Not measured | 93.3% | Only GPT-5.6 Terra measured |
| LMCA | Not measured | 54.9% | Only GPT-5.6 Terra measured |
| Surface Evolver Bench | Not measured | 83.8% | Only GPT-5.6 Terra measured |
| Furniture assembly | Not measured | 54.2% | Only GPT-5.6 Terra measured |
| LMArena Text | 1384 | 1448 | GPT-5.6 Terra |
| LMArena Text: instruction following | 1354 | 1456 | GPT-5.6 Terra |
| LMArena Text: creative writing | 1343 | 1413 | GPT-5.6 Terra |
| LMArena Vision | Not measured | 1271 | Only GPT-5.6 Terra measured |
| LMArena Text: English | 1397 | 1449 | GPT-5.6 Terra |
| LMArena Text: non-English | 1366 | 1441 | GPT-5.6 Terra |
| LMArena Text: Chinese | 1426 | 1514 | GPT-5.6 Terra |
| LMArena Text: German | 1377 | 1460 | GPT-5.6 Terra |
| LMArena Text: Japanese | 1348 | 1454 | GPT-5.6 Terra |
| LMArena Text: Korean | 1308 | 1427 | GPT-5.6 Terra |
| LMArena Text: French | 1400 | 1466 | GPT-5.6 Terra |
| LMArena Text: Spanish | 1385 | 1451 | GPT-5.6 Terra |
| LMArena Text: Russian | 1373 | 1452 | GPT-5.6 Terra |
| LMArena Text: Polish | 1368 | 1446 | GPT-5.6 Terra |
| LMArena Text: multi-turn | 1371 | 1453 | GPT-5.6 Terra |
| LMArena Text: longer queries | 1366 | 1454 | GPT-5.6 Terra |
| LMArena Text: writing and language | 1354 | 1431 | GPT-5.6 Terra |
| LMArena Text: entertainment and media | 1339 | 1418 | GPT-5.6 Terra |
| LMArena Vision: English | Not measured | 1272 | Only GPT-5.6 Terra measured |
| LMArena Vision: Chinese | Not measured | 1337 | Only GPT-5.6 Terra measured |
| LMArena Vision: reading text | Not measured | 1278 | Only GPT-5.6 Terra measured |
| LMArena Vision: humor | Not measured | 1236 | Only GPT-5.6 Terra measured |
| LMArena Vision: creative writing | Not measured | 1248 | Only GPT-5.6 Terra measured |
| LMArena Document | Not measured | 1472 | Only GPT-5.6 Terra measured |
| EQ-Bench 4 | Not measured | 1234 | Only GPT-5.6 Terra 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 | GLM 4.5 Air | GPT-5.6 Terra | 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 Air$0.0008Fits in one request
GPT-5.6 Terra$0.0080Fits in one request
GLM 4.5 Air costs less
Repository review
50K input + 3K output tokens
GLM 4.5 Air$0.013Fits in one request
GPT-5.6 Terra$0.136Fits in one request
GLM 4.5 Air costs less
Agent loop
200K input + 10K output tokens
GLM 4.5 Air$0.051Exceeds the context window
GPT-5.6 Terra$0.520Fits in one request
GLM 4.5 Air 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 | Z.ai GLM 4.5 Air | OpenAI GPT-5.6 Terra |
|---|---|---|
| Maker | Z.ai | OpenAI |
| Weights | Open weights | No public weights listed |
| Released | July 25, 2025 | July 9, 2026 |
| Context window | 131K | 1.05M |
| Input $/Mtok | $0.20 | $2.00 |
| Output $/Mtok | $1.10 | $12.00 |
| Coding index | Not benchmarked | 63.9 |
| Independent measurements behind it | 0 | 6 |
| Cost per solved task | Not computable | $0.42 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GLM 4.5 Air better than GPT-5.6 Terra for coding?
Only GPT-5.6 Terra has a coding score, 63.9 on the Vibe Coding Index; GLM 4.5 Air has none, so the two cannot be ranked on coding. Pick GLM 4.5 Air for output tokens 10.9x cheaper ($1.10 vs $12.00 per million).
Which is cheaper, GLM 4.5 Air or GPT-5.6 Terra?
GLM 4.5 Air costs $0.20 per million input tokens and $1.10 per million output tokens; GPT-5.6 Terra costs $2.00 and $12.00. Cost per solved task is known for GPT-5.6 Terra only.
Which has the bigger context window, GLM 4.5 Air or GPT-5.6 Terra?
GPT-5.6 Terra, with 1.05M tokens against 131K.
How many benchmarks is the GLM 4.5 Air vs GPT-5.6 Terra comparison based on?
43 benchmarks have a result for both models as of October 22, 2026. GLM 4.5 Air's coding index rests on 0 independent benchmarks and GPT-5.6 Terra's on 6. Where only one model has a result, the page says so instead of naming a winner.