How to Estimate AI Tokens and Cost in Excel
Before pasting ten thousand support tickets into a model, two questions matter: will this fit in the context window, and what will it cost? Both are answered in tokens, and nothing in Excel counts tokens.
Last updated: October 2026
| Comment | → | Tokens (est.) | Cost (est.) |
|---|---|---|---|
| The delivery was late and the box was damaged | → | 11 | 0.000033 |
| Great service, thank you | → | 6 | 0.000018 |
It is an estimate, and it says so everywhere
A real count needs the model's own tokenizer — a megabyte of vocabulary that differs per model family and would have to be downloaded, which is at odds with a tool that runs offline. So this estimates from the two things that drive the count: characters, at roughly four per token for ordinary English, and words, at roughly four tokens per three words. It takes the larger of the two, which errs towards over-estimating — the safer direction when the number is being used to check a budget or a context limit.
Expect it to be within about ten per cent for prose. Expect it to be worse for code, for languages that do not use spaces, and for long identifiers or runs of digits, which fragment into many more tokens than their length suggests.
Why there are no model presets
Model prices change. A price list baked into a tool is a price list that is wrong six months later, and wrong quietly. You enter the rate your provider charges today, in your own currency, and the arithmetic is yours.
The 1-click way (Tellsheet)
Token Counter
Select the text column and run Token Counter. It adds a Tokens (est.) column and, if you want it, a Cost (est.) column at the price per million you set. The summary gives the total, the largest single row — the one most likely to hit a per-request limit — and restates that these are estimates rather than a tokenizer's count.
Frequently asked questions
How accurate is it?
Within about 10% for prose; worse for code and identifiers.
Why not use the real tokenizer?
It is a megabyte of per-model vocabulary, and this runs offline.
Where do I get the price?
From your provider's current pricing — you enter it.
Does it send my text anywhere?
No. Nothing leaves the device.
Related Excel guides
Know the size before you send it
Token Counter estimates tokens and cost per row, entirely offline.
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