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Grok 4 Fast token counter

Type or paste a prompt to count Grok 4 Fast tokens and estimate what it costs to run — free, live, and private.

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Grok 4 Fast

xAI · 2M context
tokens

About Grok 4 Fast tokenization

Vendor
xAI
Context window
2M tokens
Pricing (per 1M tokens)
$0.2 input · $0.5 output (as of 2026-07-07)
How we count
xAI's official count-tokens API, since its tokenizer isn't public

FAQ

How accurate is this Grok 4 Fast token count?

Exact when a server API key is configured — counts come from xAI's own count-tokens endpoint. Otherwise a clearly-labeled local estimate is shown.

Does my prompt leave the browser?

Only to xAI's count-tokens API (which doesn't run the model or store your prompt) — nothing is logged by this site.

What does a Grok 4 Fast request cost?

Input tokens × $0.2/1M plus output tokens × $0.5/1M (standard tier, as of 2026-07-07). The calculator above does this for your actual prompt.

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