# Claude Mythos Preview vs GLM-5.3

> Side-by-side benchmark comparison for Claude Mythos Preview and GLM-5.3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-mythos-preview-vs-glm-5-3
- Last updated: September 28, 2026

- Shared sourced benchmarks: 2
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Evidence is too thin for a benchmark verdict: Claude Mythos Preview and GLM-5.3 share only 2 sourced benchmark rows.

## Summary

- Only 2 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- GLM-5.3 has the lower published output-token price.
- GLM-5.3 has the larger published context window at 1M.

## Model Snapshot

| Property | Claude Mythos Preview | GLM-5.3 |
|----------|----------|----------|
| Creator | Anthropic | Z.AI |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | null | 1M |
| Independent public score (not head-to-head) | null | 65.44 |
| Benchmarks Covered | 2 | 24 |
| Pricing (input/output) | $25.00 / $125.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- GLM-5.3 public-lane score: 67.4 (Supported · #9/117)

| Benchmark | Claude Mythos Preview | GLM-5.3 | Winner |
|-----------|-----------|-----------|--------|
| CyberGym | 83.1% | 84.5% | GLM-5.3 |
| ExploitGym | 17.5% | 15.0% | Claude Mythos Preview |
| Terminal-Bench 2.1 | Coming soon | 88.2% | Coming soon |
| terminalBench3 | Coming soon | 28.3% | Coming soon |
| Toolathlon-Verified | Coming soon | 73.0% | Coming soon |
| AutomationBench | Coming soon | 48.2% | Coming soon |
| Agents' Last Exam | Coming soon | 28.5% | Coming soon |
| HLE w/ tools | Coming soon | 62.5% | Coming soon |
| Terminal-Bench 2.1 (Vals) | Coming soon | 71.5% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- GLM-5.3 public-lane score: 56.8 (Supported · #24/142)

| Benchmark | Claude Mythos Preview | GLM-5.3 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | Coming soon | 88.2% | Coming soon |
| terminalBench3 | Coming soon | 28.3% | Coming soon |
| DeepSWE | Coming soon | 66.9% | Coming soon |
| NL2Repo | Coming soon | 58% | Coming soon |
| ProgramBench | Coming soon | 19.0% | Coming soon |
| FrontierSWE | Coming soon | 78.1% | Coming soon |
| sweMarathon | Coming soon | 42.5% | Coming soon |
| PostTrain Bench | Coming soon | 39.8% | Coming soon |
| VulcanBench v3 | Coming soon | 78.3% | Coming soon |
| OpenHarmony Bench | Coming soon | 60.8% | Coming soon |
| FrontierSWE v2 | Coming soon | 30.2% | Coming soon |
| LiveCodeBench (Vals) | Coming soon | 80.5% | Coming soon |
| SWE-bench (Vals) | Coming soon | 95.4% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- GLM-5.3 public-lane score: 77.1 (#11/27)

### Knowledge

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- GLM-5.3 public-lane score: 61.9 (Supported · #35/168)

| Benchmark | Claude Mythos Preview | GLM-5.3 | Winner |
|-----------|-----------|-----------|--------|
| GPQA Diamond (Vals) | Coming soon | 88.1% | Coming soon |
| MMLU-Pro (Vals) | Coming soon | 86.8% | Coming soon |

## FAQ

### Is there enough evidence to pick between Claude Mythos Preview and GLM-5.3?

Not yet. The models share only 2 sourced benchmark rows, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Claude Mythos Preview vs Claude Mythos 5](/compare/claude-mythos-5-vs-claude-mythos-preview)
- [GLM-5.3 vs Claude Mythos 5](/compare/claude-mythos-5-vs-glm-5-3)
- [Claude Mythos Preview vs Claude Mythos 5.1](/compare/claude-mythos-5-1-vs-claude-mythos-preview)
- [GLM-5.3 vs Claude Mythos 5.1](/compare/claude-mythos-5-1-vs-glm-5-3)

## Explore More

- [Claude Mythos Preview profile](/models/claude-mythos-preview)
- [GLM-5.3 profile](/models/glm-5-3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)