Model comparison
Claude Mythos Preview vs GLM-5.3-Flash
GLM-5.3-Flash has enough public results to be ranked (#45); Claude Mythos Preview does not yet, so treat this comparison as directional.
Last verified . 0 shared benchmarks.
Summary
- The widest gap is in agentic & tool use, where Claude Mythos Preview leads 41.1 to 34.3.
- GLM-5.3-Flash has downloadable open weights; the other is API-only.
Side by side
| Claude Mythos Preview | GLM-5.3-Flash | |
|---|---|---|
| Provider | Anthropic | Z.ai (Zhipu) |
| Noometry Index | 40.8 | 49.6 |
| Released | 2026-04-07 | 2026-08-20 |
| Weights | Proprietary | Open |
| Context window | — | 1M |
| Max output | — | 131K |
| Input $ / M tokens | — | $0.15 |
| Output $ / M tokens | — | $0.50 |
| Results tracked | 2 | 36 |
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Category by category
Coding Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 53.7 (#26)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| DeepSWE | — | 63.4% |
| FrontierCode | — | 31.8% |
| LMArena WebDev | — | 1614 |
| SciCode | — | 51.6% |
| LMArena Coding | — | 1506 |
| ALE-Bench | — | 303.55 |
Agentic & Tool Use Claude Mythos Preview leads
Claude Mythos Preview: 41.1, GLM-5.3-Flash: 34.3 (#41)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| APEX-Agents | — | 52.8% |
| ExploitBench | 73.8% | — |
| GDP.pdf | — | 14% |
| METR Time Horizons | 85.2% | — |
Reasoning Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 31.7 (#69)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| CritPt | — | 15.4% |
| Chess Puzzles | — | 14% |
| LMArena Hard Prompts | — | 1490 |
| Mystery Game Puzzles | — | 8% |
| Surface Evolver Bench | — | 52.5% |
| Bench to the Future 3 | — | 0.15 |
| Epoch Capabilities Index | — | 151.9 |
Math Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 53.1 (#38)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| FrontierMath (Tiers 1-3) | — | 55.8% |
| FrontierMath Tier 4 | — | 17.1% |
| OTIS Mock AIME 2024-2025 | — | 93.9% |
| ProofBench | — | 21% |
| LMArena Math | — | 1499 |
Knowledge Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 58.4 (#33)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| GPQA Diamond | — | 90.2% |
| LMArena Expert | — | 1512 |
Multimodal Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 42.6 (#25)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| LMArena Vision | — | 1304 |
Multilingual Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 56.2 (#24)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| LMArena Non-English | — | 1462 |
| LMArena Chinese | — | 1529 |
| LMArena French | — | 1495 |
| LMArena German | — | 1457 |
| LMArena Japanese | — | 1420 |
| LMArena Korean | — | 1443 |
| LMArena Russian | — | 1472 |
| LMArena Spanish | — | 1471 |
Instruction Following Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 77.8 (#17)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| LMArena Instruction Following | — | 1480 |
Long Context Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 45.3 (#41)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| LMArena Longer Query | — | 1479 |
Writing & Preference Not comparable
Claude Mythos Preview: —, GLM-5.3-Flash: 65.4 (#49)
| Benchmark | Claude Mythos Preview | GLM-5.3-Flash |
|---|---|---|
| LMArena Text | — | 1471 |
| LMArena Creative Writing | — | 1440 |
| LMArena Multi-Turn | — | 1471 |
Frequently asked questions
Is Claude Mythos Preview better than GLM-5.3-Flash?
GLM-5.3-Flash has enough public results to be ranked (#45); Claude Mythos Preview does not yet, so treat this comparison as directional.
How many benchmarks do Claude Mythos Preview and GLM-5.3-Flash share?
0 benchmarks have published results for both models. Claude Mythos Preview has 2 scored results on Noometry and GLM-5.3-Flash has 36.