Gemini 3.8 Flash TTS vs GPT-6 Astra
A direct, empirical evaluation of Gemini 3.8 Flash TTS (Google DeepMind) against GPT-6 Astra (OpenAI).
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.
GPT-6 Astra
Developed by OpenAI · Proprietary Frontier parameters
Complex multi-step engineering, formal math proofs, autonomous computer/browser navigation, and CAD synthesis.
| Metric | Gemini 3.8 Flash TTS | GPT-6 Astra |
|---|---|---|
| SWE-bench Verified | 64.2% | 79.4% |
| MMLU-Pro | 88.5% | 91.2% |
| MATH-500 | 91% | 98.6% |
| Context Window | 128,000 characters input dialogue script | 1,050,000 tokens |
| Input Pricing (per 1M) | $0.15 | $10.00 |
| Output Pricing (per 1M) | $15.00 | $50.00 |