GLM 5.3 vs o3
GLM 5.3 
o3 Verdict
- GLM 5.3 (max) and o3 are level on quality (60.0 vs 60.5).
- GLM 5.3 (max) is stronger in coding, human preference, reasoning.
- o3 is stronger in agents & tools, knowledge, maths, composite, instruction following, long context, multimodal.
- GLM 5.3 (max) is 1.6× cheaper ($2.15 vs $3.50 per 1M blended).
- o3 streams 2.0× faster (130 vs 66 tokens per second).
| Metric | GLM 5.3 (max) | o3 |
|---|---|---|
| BenchLeader Index | 60.0 | 60.5 |
| Agents & tools score | 52.8 | 68.7 |
| Coding score | 64.3 | 62.0 |
| Human preference score | 68.9 | 62.3 |
| Knowledge score | 55.8 | 56.2 |
| Maths score | 60.0 | 78.6 |
| Reasoning score | 66.9 | 61.5 |
| Composite score | – | 49.6 |
| Instruction following score | – | 63.8 |
| Long context score | – | 60.9 |
| Multimodal score | – | 56.9 |
| Blended price $/M | $2.15 | $3.50 |
| Output speed | 66 tok/s | 130 tok/s |
| Time to first answer | 33.5 s | 4.4 s |
| Context window | 1M | 200k |
| GPQA Diamond | 90.9% | – |
| FrontierMath Tiers 1–3 | 68.8% | – |
| FrontierMath Tier 4 | 29.3% | – |
| OTIS Mock AIME | 91.1% | – |
| SimpleQA Verified | 41.0% | – |
| Terminal-Bench | 41.8% | – |
| SciCode | 56.5% | – |
| WeirdML | 75.4% | – |
| ProofBench | 49.0% | – |
| Epoch Capabilities Index | – | 146.9 |
| LMArena Text | 1486 | 1432 |
| LMArena Hard Prompts | 1509 | 1441 |
| LMArena Coding | 1526 | 1460 |
| LMArena WebDev | 1614 | – |
| LMArena Vision | – | 1214 |
| LMArena Agent | 2.6 | – |
| AA Intelligence Index | – | 20.2 |
| IFBench | – | 71.4% |
| AA-LCR | – | 74.7% |
| MMMU-Pro | – | 70.1% |
| AA-Omniscience | – | -15.6 |
| Terminal-Bench Hard | – | 37.1% |
| GPQA Diamond (AA) | – | 82.7% |
| Humanity's Last Exam (AA) | – | 20.1% |
| τ²-Bench Telecom (AA) | – | 80.7% |
| LiveCodeBench | 80.5% | – |
| MMLU-Pro | 86.8% | – |
| IOI | 68.4% | – |
| LegalBench | 84.8% | – |
| TaxEval | 72.4% | – |
| Terminal-Bench 2.1 (Vals) | 71.5% | – |
| SWE-bench (Vals) | 95.4% | – |
| GPQA Diamond (Vals) | 88.1% | – |
| Vals Index | 57.0 | – |
| PRBench Finance | – | 47.7% |
| PRBench Legal | – | 48.6% |
| MMMU (validation) | – | 82.9% |
| MMMU-Pro (official) | – | 76.4% |
| Kagi LLM Benchmark | – | 67.6% |
| IFEval (HELM) | – | 86.9% |
| Omni-MATH (HELM) | – | 71.4% |
| WildBench (HELM) | – | 86.1% |
| MMLU-Pro (HELM) | – | 85.9% |
| GPQA Diamond (HELM) | – | 75.3% |
| HELM Capabilities mean | – | 81.1% |
| Aider Polyglot | – | 81.3% |
| SWE-bench Verified (bash only) | – | 58.4% |
| SWE-bench Verified (any scaffold) | – | 58.4% |
| BFCL Overall | – | 63.0% |
Data as of 2026-09-13. Best configuration of each model; every score links to its source on the model pages.
GLM 5.3 vs o3: questions
- Is GLM 5.3 better than o3?
- GLM 5.3 (max) and o3 are level on quality (60.0 vs 60.5). The BenchLeader Index combines every independent quality benchmark; o3 is ahead overall as of 2026-09-13, but check the category scores for your use.
- Is GLM 5.3 better than o3 for coding?
- GLM 5.3 scores higher in coding (64 vs 62 on the category index, where 50 is average).
- Is GLM 5.3 better than o3 for agentic tasks?
- o3 scores higher in agentic tasks (69 vs 53 on the category index, where 50 is average).
- Which is cheaper, GLM 5.3 or o3?
- GLM 5.3 is cheaper: $2.15 against $3.50 per million tokens, blended at three input tokens per output token.
- Which is faster, GLM 5.3 or o3?
- o3 streams faster: 130 against 66 output tokens per second.
- Which has the larger context window?
- GLM 5.3 accepts more context: 1M against 200k tokens.