Claude Fable 5.5 (Leaked Checkpoint) vs DeepSeek V5 (Leaked Staging)
A direct, empirical evaluation of Claude Fable 5.5 (Leaked Checkpoint) (Anthropic) against DeepSeek V5 (Leaked Staging) (DeepSeek AI).
Claude Fable 5.5 (Leaked Checkpoint)
Developed by Anthropic · Proprietary Frontier Dynamic Reasoner parameters
Terminal-Bench 4.0 autonomous shell execution (78.5% target), recursive self-critique, and 1.5M-token repository refactoring.
DeepSeek V5 (Leaked Staging)
Developed by DeepSeek AI · 1.8 Trillion (Sparse MoE) parameters
Autonomous coding agents scoring 81.4% on SWE-bench Verified, zero-telemetry self-hosting, sub-cent 1M-token processing, and formal mathematical proofs.
| Metric | Claude Fable 5.5 (Leaked Checkpoint) | DeepSeek V5 (Leaked Staging) |
|---|---|---|
| SWE-bench Verified | 84.2% | 81.4% |
| MMLU-Pro | 94.6% | 87.5% |
| MATH-500 | 98.4% | 96.8% |
| Context Window | 1,500,000 tokens | 1,000,000 tokens |
| Input Pricing (per 1M) | $3.50 | $0.12 |
| Output Pricing (per 1M) | $17.50 | $0.48 |