GLM 5.1 vs GPT-4o (2024-08-06)
Updated October 21, 2026. 45 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 5.1 for coding: it scores 44.0 on the Vibe Coding Index against 23.1 for GPT-4o (2024-08-06).
GPT-4o (2024-08-06) is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
- Shared results
- 45
- GLM 5.1 only
- 44
- GPT-4o (2024-08-06) only
- 13
- 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
GLM 5.1
GLM 5.1 scores 44.0 against 23.1.
One benchmark behind each score
Intelligence
AA Intelligence Index
GLM 5.1
GLM 5.1 leads, 26.1 against 7.7.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GLM 5.1 has a AA Agentic Index result, 23.9.
Directional only
Reasoning
GPQA Diamond
No call
Only GLM 5.1 has a GPQA Diamond result, 84.5%.
Directional only
Math
AIME
GLM 5.1
GLM 5.1 leads, 91.9% against 14.0%.
Same board, both measured
Knowledge
MMLU Pro
GLM 5.1
GLM 5.1 leads, 86.9% against 74.1%.
Same board, both measured
Web design
Design Arena: websites
No call
Only GLM 5.1 has a Design Arena: websites result, 1290.
Directional only
Long documents
Listed context window
GLM 5.1
GLM 5.1 takes 205K tokens against 128K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
GLM 5.1
GLM 5.1 $0.0036, GPT-4o (2024-08-06) $0.0075 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GLM 5.1 has the number, $0.60.
Directional only
At a glance
- Coding index
- GLM 5.1 44.0 from 1 benchmark, GPT-4o (2024-08-06) 23.1 from 1 benchmark.
- Widest category
- Agentic work, 68.7 points apart on average over 1 shared benchmark.
- Widest single gap
- OTIS Mock AIME: GLM 5.1 93.3% against GPT-4o (2024-08-06) 6.4%, 86.9 points apart on a 0 to 100 scale.
- Output price
- GLM 5.1 $4.40 against GPT-4o (2024-08-06) $10.00 per million output tokens, 2.3x apart.
- Context window
- GLM 5.1 takes 205K tokens, GPT-4o (2024-08-06) 128K.
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 5.1 | Bars | GPT-4o (2024-08-06) | Ties |
|---|---|---|---|---|
| Coding | 3 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 8 | 0 | ||
| Math | 5 | 0 | ||
| Knowledge | 9 | 0 | ||
| General | 18 | 0 | ||
| All shared boards | 45 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index30
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 23.1% | Only GPT-4o (2024-08-06) measured |
| SWE-bench Lite | Not measured | 21.7% | Only GPT-4o (2024-08-06) measured |
| LMArena WebDev | 1508 | Not measured | Only GLM 5.1 measured |
| AA Coding Index | 55.8 | Not measured | Only GLM 5.1 measured |
| LiveCodeBench (Vals AI) | 81.4% | Not measured | Only GLM 5.1 measured |
| SWE-bench Verified (Vals AI) | 76.4% | Not measured | Only GLM 5.1 measured |
| Vibe Code Bench (Vals AI) | 31.5% | Not measured | Only GLM 5.1 measured |
| Code migration (Vals AI) | 25.8% | Not measured | Only GLM 5.1 measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only GLM 5.1 measured |
| Terminal-Bench 2.1 (Vals AI) | 56.9% | Not measured | Only GLM 5.1 measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 31.7% | Only GPT-4o (2024-08-06) measured |
| SciCode | 44.8% | Not measured | Only GLM 5.1 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 43.2% | 8.3% | GLM 5.1 |
| WeirdML | 57.1% | Not measured | Only GLM 5.1 measured |
| ALE-Bench | 887.1 | Not measured | Only GLM 5.1 measured |
| LMArena Text: coding | 1485 | 1283 | GLM 5.1 |
| LMArena Text: software and IT | 1484 | 1278 | GLM 5.1 |
| LMArena WebDev: React | 1505 | Not measured | Only GLM 5.1 measured |
| LMArena WebDev: HTML | 1508 | Not measured | Only GLM 5.1 measured |
| Neither model has a result on the other 19 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.1 | 7.7 | GLM 5.1 |
| Epoch Capabilities Index | 149.8 | Not measured | Only GLM 5.1 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| AA Agentic Index | 23.9 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building web apps | 1175 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building full-stack apps | 1167 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building mobile apps | 1162 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building Android apps | 1186 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building Godot games | 1053 | Not measured | Only GLM 5.1 measured |
| Design Arena: agents building games | 1164 | Not measured | Only GLM 5.1 measured |
| Design Arena: HTML slides | 1170 | Not measured | Only GLM 5.1 measured |
| Design Arena: PowerPoint slides | 1189 | Not measured | Only GLM 5.1 measured |
| Design Arena: spreadsheets | 1315 | Not measured | Only GLM 5.1 measured |
| Finance Agent (Vals AI) | 44.8% | Not measured | Only GLM 5.1 measured |
| Legal Research Bench (Vals AI) | 27.9% | Not measured | Only GLM 5.1 measured |
| τ²-Bench Telecom | 97.7% | 28.9% | GLM 5.1 |
| APEX-Agents | 40.9% | Not measured | Only GLM 5.1 measured |
| Vending-Bench 2 | $5,634 | Not measured | Only GLM 5.1 measured |
| Neither model has a result on the other 24 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| GPQA Diamond | 84.5% | Not measured | Only GLM 5.1 measured |
| MMMU Pro (Vals AI) | Not measured | 64.0% | Only GPT-4o (2024-08-06) measured |
| GPQA Diamond (Artificial Analysis run) | 86.8% | 52.1% | GLM 5.1 |
| Humanity's Last Exam (Artificial Analysis run) | 30.1% | 2.3% | GLM 5.1 |
| GPQA Diamond (Epoch AI run) | 89.9% | 49.2% | GLM 5.1 |
| SimpleBench | 55.1% | 17.8% | GLM 5.1 |
| Chess puzzles | 20.0% | 6.0% | GLM 5.1 |
| LMArena Text: hard prompts | 1473 | 1264 | GLM 5.1 |
| LMArena Text: expert | 1478 | 1241 | GLM 5.1 |
| LMArena Text: hard prompts in English | 1482 | 1277 | GLM 5.1 |
| Neither model has a result on the other 11 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| AIME | 91.9% | 14.0% | GLM 5.1 |
| MATH 500 (Vals AI) | Not measured | 75.2% | Only GPT-4o (2024-08-06) measured |
| MGSM (Vals AI) | Not measured | 90.7% | Only GPT-4o (2024-08-06) measured |
| OTIS Mock AIME | 93.3% | 6.4% | GLM 5.1 |
| FrontierMath, tiers 1 to 3 | 36.8% | 0.4% | GLM 5.1 |
| ProofBench | 22.2% | Not measured | Only GLM 5.1 measured |
| MATH level 5 | Not measured | 53.3% | Only GPT-4o (2024-08-06) measured |
| LMArena Text: math | 1473 | 1285 | GLM 5.1 |
| LMArena Text: mathematical work | 1470 | 1283 | GLM 5.1 |
| Neither model has a result on the other 4 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index90
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| MMLU Pro | 86.9% | 74.1% | GLM 5.1 |
| LegalBench (Vals AI) | 84.4% | 80.1% | GLM 5.1 |
| CaseLaw (Vals AI) | 51.5% | Not measured | Only GLM 5.1 measured |
| CorpFin (Vals AI) | 64.5% | 39.4% | GLM 5.1 |
| TaxEval (Vals AI) | 71.2% | 71.1% | GLM 5.1 |
| MortgageTax (Vals AI) | Not measured | 61.0% | Only GPT-4o (2024-08-06) measured |
| MedQA (Vals AI) | Not measured | 88.2% | Only GPT-4o (2024-08-06) measured |
| MedCode (Vals AI) | 41.6% | Not measured | Only GLM 5.1 measured |
| SimpleQA Verified | 34.0% | 26.0% | GLM 5.1 |
| MMLU | Not measured | 84.3% | Only GPT-4o (2024-08-06) measured |
| LMArena Text: science | 1478 | 1274 | GLM 5.1 |
| LMArena Text: medicine and healthcare | 1474 | 1252 | GLM 5.1 |
| LMArena Text: legal and government | 1465 | 1275 | GLM 5.1 |
| LMArena Text: business and finance | 1452 | 1232 | GLM 5.1 |
| Neither model has a result on the other 3 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| Design Arena: websites | 1290 | Not measured | Only GLM 5.1 measured |
| Design Arena: UI components | 1292 | Not measured | Only GLM 5.1 measured |
| Design Arena: game dev | 1265 | Not measured | Only GLM 5.1 measured |
| Design Arena: data viz | 1366 | Not measured | Only GLM 5.1 measured |
| Design Arena: 3D | 1336 | Not measured | Only GLM 5.1 measured |
| Design Arena: all code categories | 1268 | Not measured | Only GLM 5.1 measured |
| Design Arena: SVG | 1217 | Not measured | Only GLM 5.1 measured |
| Design Arena: ASCII art | 1142 | Not measured | Only GLM 5.1 measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index180
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | Leader |
|---|---|---|---|
| Public Benefits Bench (Vals AI) | 61.8% | Not measured | Only GLM 5.1 measured |
| MedScribe (Vals AI) | 72.3% | Not measured | Only GLM 5.1 measured |
| IFBench | 76.3% | 36.0% | GLM 5.1 |
| Long context reasoning (AA-LCR) | 73.7% | 41.0% | GLM 5.1 |
| ExploitBench | 18.1% | Not measured | Only GLM 5.1 measured |
| LMArena Text | 1463 | 1283 | GLM 5.1 |
| LMArena Text: instruction following | 1453 | 1267 | GLM 5.1 |
| LMArena Text: creative writing | 1453 | 1274 | GLM 5.1 |
| LMArena Vision | Not measured | 1065 | Only GPT-4o (2024-08-06) measured |
| LMArena Text: English | 1476 | 1297 | GLM 5.1 |
| LMArena Text: non-English | 1448 | 1262 | GLM 5.1 |
| LMArena Text: Chinese | 1515 | 1254 | GLM 5.1 |
| LMArena Text: German | 1467 | 1257 | GLM 5.1 |
| LMArena Text: Japanese | 1435 | 1234 | GLM 5.1 |
| LMArena Text: Korean | 1424 | 1218 | GLM 5.1 |
| LMArena Text: French | 1470 | 1263 | GLM 5.1 |
| LMArena Text: Spanish | 1468 | 1269 | GLM 5.1 |
| LMArena Text: Russian | 1454 | 1272 | GLM 5.1 |
| LMArena Text: Polish | 1449 | Not measured | Only GLM 5.1 measured |
| LMArena Text: multi-turn | 1473 | 1279 | GLM 5.1 |
| LMArena Text: longer queries | 1467 | 1283 | GLM 5.1 |
| LMArena Text: writing and language | 1454 | 1290 | GLM 5.1 |
| LMArena Text: entertainment and media | 1442 | 1267 | GLM 5.1 |
| LMArena Vision: English | Not measured | 1072 | Only GPT-4o (2024-08-06) measured |
| LMArena Vision: Chinese | Not measured | 1009 | Only GPT-4o (2024-08-06) measured |
| Neither model has a result on the other 21 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GLM 5.1 | GPT-4o (2024-08-06) | 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 5.1 costs less
Repository review
50K input + 3K output tokens
GLM 5.1 costs less
Agent loop
200K input + 10K output tokens
GLM 5.1 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 5.1 | OpenAI GPT-4o (2024-08-06) |
|---|---|---|
| Maker | Z.ai | OpenAI |
| Weights | Open weights | No public weights listed |
| Released | April 7, 2026 | August 6, 2024 |
| Context window | 205K | 128K |
| Input $/Mtok | $1.40 | $2.50 |
| Output $/Mtok | $4.40 | $10.00 |
| Coding index | 44.0 | 23.1 |
| Independent measurements behind it | 1 | 1 |
| Cost per solved task | $0.60 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GLM 5.1 better than GPT-4o (2024-08-06) for coding?
Pick GLM 5.1 for coding: it scores 44.0 on the Vibe Coding Index against 23.1 for GPT-4o (2024-08-06). GPT-4o (2024-08-06) is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Which is cheaper, GLM 5.1 or GPT-4o (2024-08-06)?
GLM 5.1 costs $1.40 per million input tokens and $4.40 per million output tokens; GPT-4o (2024-08-06) costs $2.50 and $10.00. Cost per solved task is known for GLM 5.1 only.
Which has the bigger context window, GLM 5.1 or GPT-4o (2024-08-06)?
GLM 5.1, with 205K tokens against 128K.
How many benchmarks is the GLM 5.1 vs GPT-4o (2024-08-06) comparison based on?
45 benchmarks have a result for both models as of October 21, 2026. GLM 5.1's coding index rests on 1 independent benchmark and GPT-4o (2024-08-06)'s on 1. Where only one model has a result, the page says so instead of naming a winner.