Compare models
Put up to 4 models beside each other — token prices, context windows, capabilities and provider, from the same catalogue the model pages read.
4 is the maximum. Remove one to add another.
| Attribute | GPT-6 Astragpt-6-astra | S2 Pros2-pro | Transcribe 1 Protranscribe-1-pro | GPT-6 Lunagpt-6-luna |
|---|---|---|---|---|
| Pricing | ||||
| Input | $10.00 / 1M | $0 / 1M | $0 / 1M | $0.10 / 1M |
| Output | $50.00 / 1M | $0 / 1M | $0 / 1M | $0.50 / 1M |
| Cache Write (5m) | $10.00 / 1M | Not applicable | Not applicable | $0.10 / 1M |
| Cache Write (1h) | $10.00 / 1M | Not applicable | Not applicable | $0.10 / 1M |
| Cache Read | $10.00 / 1M | Not applicable | Not applicable | $0.10 / 1M |
| Web Search | $0 / 1M | $0 / 1M | $0 / 1M | $0 / 1M |
| Context | ||||
| Max context | 1M | N/A | N/A | 1.1M |
| Max output | N/A | N/A | N/A | N/A |
| Capabilities | ||||
| Vision | Yes | No | No | Yes |
| Function Calling | Yes | No | No | Yes |
| JSON Mode | Yes | No | No | Yes |
| Streaming | Yes | No | No | Yes |
| Catalogue | ||||
| Provider | OpenAI | Fish Audio | Fish Audio | OpenAI |
| Category | chat | voice | voice | chat |
| Charge type | Pay As You Go | Pay As You Go | Pay As You Go | Pay As You Go |
| Released | — | 2026-07-29 | 2026-09-24 | — |
| Description | ||||
| Summary | GPT-6 Astra is OpenAI's flagship model for demanding end-to-end professional work, designed for advanced analysis, software engineering, deep research, scientific tasks, and document creation. It is particularly strong in long-horizon agentic workflows, including tasks that require sustained reasoning, tool orchestration, and computer and browser use, making it well suited for complex autonomous workflows and production-grade knowledge work. | Fish Audio S2 Pro text-to-speech. Billed per UTF-8 byte of input text. | Fish Audio Transcribe 1 Pro speech-to-text with speaker labels; transcripts include speaker tags such as <|speaker:0|>. Billed per second of audio. | GPT-6 Luna is the fast, cost-efficient model in OpenAI's GPT-6 series, optimized for high-volume and latency-sensitive workloads such as chat, classification, and lightweight agentic tasks. It combines low-cost, responsive inference with the GPT-6 family’s improvements in factual reliability and clear, concise communication. At higher reasoning effort, GPT-6 Luna can also handle complex software engineering and computer-use workflows that previously required a Sol-tier model, making it a versatile choice for scalable production applications that need to balance speed, cost, and capability. |