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GPT-4o mini token counter

Type or paste a prompt to count GPT-4o mini tokens and estimate what it costs to run — free, live, and private.

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Counts include each model's own chat-template overhead.

128 chars

GPT-4o mini

OpenAI · 128k context
tokens

About GPT-4o mini tokenization

Vendor
OpenAI
Context window
128k tokens
Pricing (per 1M tokens)
$0.15 input · $0.6 output (as of 2026-07-07)
How we count
the o200k_base encoding, running entirely in your browser

FAQ

How accurate is this GPT-4o mini token count?

Exact — it uses the o200k_base encoding, running entirely in your browser, the same tokenizer the model uses in production.

Does my prompt leave the browser?

No. Tokenization runs entirely in your browser.

What does a GPT-4o mini request cost?

Input tokens × $0.15/1M plus output tokens × $0.6/1M (standard tier, as of 2026-07-07). The calculator above does this for your actual prompt.

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