Model overview
Four of the six xAI entries share one rate card, and this is the one that is not a 4.20 variant: $1.25 per million input tokens, $0.20 cached, $2.50 output, over a 1,000,000-token window. Set against grok-4-5 that is 37.5 percent less on input, under half the output rate, and twice the context; set against the cheaper build model it is 25 percent more on both meters for roughly four times the window. Since grok-4-3 costs exactly what the reasoning, non-reasoning and multi-agent 4.20 builds cost, the comparison with them is behavioural rather than financial. Note the long-context rule: at 200,000 input tokens or more, xAI's published long-context rates apply to every token in the request, not just the excess.
Billing conditions: Standard short-context API price. At 200K input tokens or more, xAI applies its published long-context rates to all tokens in the request.
- Context window
- 1,000,000 tokens
- Knowledge cutoff
- —
- Price last verified
- First observed
Descriptions, capabilities, and tariffs come from the linked source. First-party prices take priority; OpenRouter fallbacks are labelled.