Compare models
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| Attribute | GPT-6 Sol Progpt-6-sol-pro | Universal-3.5 Prouniversal-3-5-pro | S1s1 | S2 Pros2-pro |
|---|---|---|---|---|
| Pricing | ||||
| Input | $2.00 / 1M | $0 / 1M | $0 / 1M | $0 / 1M |
| Output | $10.00 / 1M | $0 / 1M | $0 / 1M | $0 / 1M |
| Cache Write (5m) | $2.00 / 1M | Not applicable | Not applicable | Not applicable |
| Cache Write (1h) | $2.00 / 1M | Not applicable | Not applicable | Not applicable |
| Cache Read | $2.00 / 1M | Not applicable | Not applicable | Not applicable |
| Web Search | $0 / 1M | $0 / 1M | $0 / 1M | $0 / 1M |
| Context | ||||
| Max context | 1.1M | N/A | N/A | N/A |
| Max output | N/A | N/A | N/A | N/A |
| Capabilities | ||||
| Vision | Yes | No | No | No |
| Function Calling | Yes | No | No | No |
| JSON Mode | Yes | No | No | No |
| Streaming | Yes | No | No | No |
| Catalogue | ||||
| Provider | OpenAI | AssemblyAI | Fish Audio | Fish Audio |
| Category | chat | voice | voice | voice |
| Charge type | Pay As You Go | Pay As You Go | Pay As You Go | Pay As You Go |
| Released | — | 2026-09-22 | 2026-07-29 | 2026-07-29 |
| Description | ||||
| Summary | GPT-6 Sol Pro uses the same underlying model as GPT-6 Sol, but runs with reasoning.mode set to pro for higher-quality responses on complex and demanding tasks. Optimized for deeper reasoning, greater accuracy, and more reliable multi-step execution, it is particularly well suited for agentic coding, long-horizon software engineering, professional analysis, and complex automated workflows where solution quality takes priority over latency and cost. | AssemblyAI Universal-3.5 Pro speech-to-text. Billed per second of audio. | Fish Audio S1 text-to-speech. Billed per UTF-8 byte of input text. | Fish Audio S2 Pro text-to-speech. Billed per UTF-8 byte of input text. |