# Claude Mythos Preview vs DeepSeek V3

> Side-by-side benchmark comparison for Claude Mythos Preview and DeepSeek V3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-mythos-preview-vs-deepseek-v3
- Last updated: September 29, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for Claude Mythos Preview and DeepSeek V3.

## Summary

- Claude Mythos Preview and DeepSeek V3 do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | Claude Mythos Preview | DeepSeek V3 |
|----------|----------|----------|
| Creator | Anthropic | DeepSeek |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Non-Reasoning |
| Context | null | 128K |
| Independent public score (not head-to-head) | null | 31.86 |
| Benchmarks Covered | 2 | 6 |
| Pricing (input/output) | $25.00 / $125.00 | $0.27 / $1.10 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 12.1 (Estimated · #113/117)

| Benchmark | Claude Mythos Preview | DeepSeek V3 | Winner |
|-----------|-----------|-----------|--------|
| CyberGym | 83.1% | Coming soon | Coming soon |
| ExploitGym | 17.5% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 18.6 (Estimated · #131/143)

| Benchmark | Claude Mythos Preview | DeepSeek V3 | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench | Coming soon | 37.6% | Coming soon |
| SWE-bench Verified | Coming soon | 42% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 42.3 (Unranked · 2 rankable rows)

### Knowledge

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 30.2 (Estimated · #140/169)

| Benchmark | Claude Mythos Preview | DeepSeek V3 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | Coming soon | 59.1% | Coming soon |
| MMLU-Pro | Coming soon | 75.9% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 38.2 (#103/124)

| Benchmark | Claude Mythos Preview | DeepSeek V3 | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 86.1% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- Claude Mythos Preview public-lane score: Coming soon
- DeepSeek V3 public-lane score: 26 (Unranked · 1 rankable row)

| Benchmark | Claude Mythos Preview | DeepSeek V3 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 1.724% | Coming soon |

## FAQ

### Can I compare Claude Mythos Preview and DeepSeek V3 on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [Claude Mythos Preview vs Claude Mythos 5](/compare/claude-mythos-5-vs-claude-mythos-preview)
- [DeepSeek V3 vs Claude Mythos 5](/compare/claude-mythos-5-vs-deepseek-v3)
- [Claude Mythos Preview vs Claude Mythos 5.1](/compare/claude-mythos-5-1-vs-claude-mythos-preview)
- [DeepSeek V3 vs Claude Mythos 5.1](/compare/claude-mythos-5-1-vs-deepseek-v3)

## Explore More

- [Claude Mythos Preview profile](/models/claude-mythos-preview)
- [DeepSeek V3 profile](/models/deepseek-v3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)