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.
- S2.1 ProFish AudioRemove
- GPT-6 Luna ProOpenAIRemove
- Perceptron Mk1.5PerceptronRemove
- GPT-6 SolOpenAIRemove
4 is the maximum. Remove one to add another.
| Attribute | S2.1 Pros2.1-pro | GPT-6 Luna Progpt-6-luna-pro | Perceptron Mk1.5perceptron-mk1.5 | GPT-6 Solgpt-6-sol |
|---|---|---|---|---|
| Pricing | ||||
| Input | $0 / 1M | $0.10 / 1M | $0.15 / 1M | $2.00 / 1M |
| Output | $0 / 1M | $0.50 / 1M | $1.50 / 1M | $10.00 / 1M |
| Cache Write (5m) | Not applicable | $0.10 / 1M | $0.15 / 1M | $2.00 / 1M |
| Cache Write (1h) | Not applicable | $0.10 / 1M | $0.15 / 1M | $2.00 / 1M |
| Cache Read | Not applicable | $0.10 / 1M | $0.15 / 1M | $2.00 / 1M |
| Web Search | $0 / 1M | $0 / 1M | $0 / 1M | $0 / 1M |
| Context | ||||
| Max context | N/A | 1.1M | 36.9K | 1.1M |
| Max output | N/A | N/A | N/A | N/A |
| Capabilities | ||||
| Vision | No | Yes | No | Yes |
| Function Calling | No | Yes | No | Yes |
| JSON Mode | No | Yes | No | Yes |
| Streaming | No | Yes | Yes | Yes |
| Catalogue | ||||
| Provider | Fish Audio | OpenAI | Perceptron | OpenAI |
| Category | voice | chat | chat | chat |
| Charge type | Pay As You Go | Pay As You Go | Pay As You Go | Pay As You Go |
| Released | 2026-07-29 | — | 2026-09-25 | — |
| Description | ||||
| Summary | Fish Audio S2.1 Pro text-to-speech. Billed per UTF-8 byte of input text. | GPT-6 Luna Pro uses the same underlying model as GPT-6 Luna, but runs with reasoning.mode set to pro for higher-quality responses on complex tasks. It combines Luna's speed and cost efficiency with deeper reasoning and more reliable multi-step execution, making it well suited for advanced coding, computer use, and agentic workflows where higher solution quality is needed without moving to a larger GPT-6 tier. | Perceptron Mk1.5 chat model that accepts audio input. Audio and text input are billed per token. | GPT-6 Sol is OpenAI's cost-efficient high-end model in the GPT-6 series, positioned between the flagship GPT-6 Astra and the fast GPT-6 Luna tier. It is designed for professional knowledge work, agentic coding, business workflow automation, and computer-use tasks, with particular strength in long-horizon software engineering across real-world codebases. GPT-6 Sol approaches Astra-level factual reliability at a significantly lower cost, while sharing its clear and concise communication style. This balance of capability, reliability, and efficiency makes it well suited for production agents, complex engineering workflows, and scalable professional applications |