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.
| Attribute | Grok 4.20 Betagrok-4.20-beta | GPT-6 Lunagpt-6-luna | Universal-3.5 Prouniversal-3-5-pro |
|---|---|---|---|
| Pricing | |||
| Input | $2.00 / 1M | $0.10 / 1M | — Not priced per input token |
| Output | $6.00 / 1M | $0.50 / 1M | — Not priced per output token |
| Cache Write (5m) | $2.00 / 1M | $0.10 / 1M | Not applicable |
| Cache Write (1h) | $2.00 / 1M | $0.10 / 1M | Not applicable |
| Cache Read | $2.00 / 1M | $0.10 / 1M | Not applicable |
| Web Search | $0 / 1M | $0 / 1M | $0 / 1M |
| Context | |||
| Max context | 2M | 1.1M | N/A |
| Max output | N/A | N/A | N/A |
| Capabilities | |||
| Vision | Yes | Yes | No |
| Function Calling | Yes | Yes | No |
| JSON Mode | Yes | Yes | No |
| Streaming | Yes | Yes | No |
| Catalogue | |||
| Provider | xAI | OpenAI | AssemblyAI |
| Category | chat | chat | voice |
| Charge type | Pay As You Go | Pay As You Go | Pay As You Go |
| Released | — | — | 2026-09-22 |
| Description | |||
| Summary | Grok 4.20 Beta is xAI's newest flagship model, designed for high-performance reasoning with industry-leading speed and strong agentic tool-calling capabilities. It emphasizes strict prompt adherence and low hallucination rates, enabling highly reliable and precise responses across complex tasks. Optimized for agent workflows and real-time applications, Grok 4.20 Beta delivers consistent, truthful outputs while maintaining fast inference and strong task execution reliability. | 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. | AssemblyAI Universal-3.5 Pro speech-to-text. Billed per second of audio. |