Gemini 3.8 Flash TTS vs GPT-Image-2.5 (Sunburst)
A direct, empirical evaluation of Gemini 3.8 Flash TTS (Google DeepMind) against GPT-Image-2.5 (Sunburst) (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-Image-2.5 (Sunburst)
Developed by OpenAI · Proprietary Multimodal DiT parameters
High-fidelity typographic rendering, raytracing reflection accuracy, sketch-to-image conditioning, and localized comment inpainting.
| Metric | Gemini 3.8 Flash TTS | GPT-Image-2.5 (Sunburst) |
|---|---|---|
| SWE-bench Verified | 64.2% | 62.4% |
| MMLU-Pro | 88.5% | 89.5% |
| MATH-500 | 91% | 91.2% |
| Context Window | 128,000 characters input dialogue script | Spatial Vector Token Canvas (1792×1024) |
| Input Pricing (per 1M) | $0.15 | $2.50 |
| Output Pricing (per 1M) | $15.00 | $10.00 |