GLM-5 vs GPT-5.5 Pro
GLM-5 
GPT-5.5 Pro Verdict
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 59.6.
- GLM-5 (thinking) is stronger in agents & tools, coding, composite, instruction following, knowledge, long context.
- GPT-5.5 Pro (xhigh) is stronger in maths, reasoning.
- GLM-5 (thinking) is 44× cheaper ($1.55 vs $67.50 per 1M blended).
- GLM-5 (thinking) streams 15.2× faster (61 vs 4 tokens per second).
| Metric | GLM-5 (thinking) | GPT-5.5 Pro (xhigh) |
|---|---|---|
| BenchLeader Index | 59.6 | 67.1 |
| Agents & tools score | 57.9 | – |
| Coding score | 59.1 | – |
| Composite score | 64.4 | – |
| Instruction following score | 70.7 | – |
| Knowledge score | 59.1 | – |
| Long context score | 64.2 | – |
| Maths score | 63.2 | 74.5 |
| Reasoning score | 53.3 | 80.1 |
| Blended price $/M | $1.55 | $67.50 |
| Output speed | 61 tok/s | 4 tok/s |
| Time to first answer | 52.4 s | 3.5 s |
| Context window | 205k | 1.1M |
| FrontierMath Tiers 1–3 | – | 87.7% |
| FrontierMath Tier 4 | – | 78.0% |
| AA Intelligence Index | 27.9 | – |
| IFBench | 72.3% | – |
| AA-LCR | 75.7% | – |
| AA-Omniscience | 0.3 | – |
| Terminal-Bench Hard | 43.2% | – |
| GPQA Diamond (AA) | 82.0% | – |
| Humanity's Last Exam (AA) | 29.3% | – |
| τ²-Bench Telecom (AA) | 98.3% | – |
| AIME (Vals) | 91.7% | – |
| LiveCodeBench | 81.9% | – |
| MMLU-Pro | 86.0% | – |
| LegalBench | 84.1% | – |
| CorpFin | 62.9% | – |
| TaxEval | 70.0% | – |
| MedQA | 94.3% | – |
| SWE-bench (Vals) | 71.4% | – |
| GPQA Diamond (Vals) | 83.3% | – |
| Kagi LLM Benchmark | 75.0% | – |
| ARC-AGI-1 | – | 95.0% |
| ARC-AGI-2 | – | 84.2% |
| τ²-bench | 81.0% | – |
| CritPt | 2.0% | 30.6% |
| APEX-Agents (AA) | 14.4% | – |
| CaseLaw v2 | 52.5% | – |
| Terminal-Bench 2.0 (Vals) | 49.4% | – |
| Vibe Code Bench v1.1 | 23.4% | – |
| LMCA | – | 53.9% |
| DTBench | – | 96.0% |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
GLM-5 vs GPT-5.5 Pro: questions
- Is GLM-5 better than GPT-5.5 Pro?
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 59.6. The BenchLeader Index combines every independent quality benchmark; GPT-5.5 Pro (xhigh) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Which is cheaper, GLM-5 or GPT-5.5 Pro?
- GLM-5 is cheaper: $1.55 against $67.50 per million tokens, blended at three input tokens per output token.
- Which is faster, GLM-5 or GPT-5.5 Pro?
- GLM-5 streams faster: 61 against 4 output tokens per second.
- Which has the larger context window?
- GPT-5.5 Pro accepts more context: 1.1M against 205k tokens.