Claude Fable 5.1 vs Gemini 3.8 Flash TTS

A direct, empirical evaluation of Claude Fable 5.1 (Anthropic) against Gemini 3.8 Flash TTS (Google DeepMind).

Claude Fable 5.1

Developed by Anthropic · Proprietary Frontier parameters

Full-repository software refactoring, agentic tool workflows, formal verification, and 1.5M-token needle retrieval.

Gemini 3.8 Flash TTS

Developed by Google DeepMind · Proprietary Multimodal Acoustic Flow Matching Transformer parameters

High-fidelity expressive podcasts, interactive video game dialogues, scripted multi-speaker conversations, and prompt-designed custom character voices.

Metric Claude Fable 5.1 Gemini 3.8 Flash TTS
SWE-bench Verified 82.8% 64.2%
MMLU-Pro 92.4% 88.5%
MATH-500 97.9% 91%
Context Window 1,500,000 tokens 128,000 characters input dialogue script
Input Pricing (per 1M) $12.00 $0.15
Output Pricing (per 1M) $60.00 $15.00