CodeKitHubWhat Is This Tool?
Checks require the amount written twice: once in numerals (in the small box) and once spelled out in words (on the long line). The written-out version exists specifically to prevent fraud — a numeral is trivial to alter, but altering a fully spelled-out phrase without it looking tampered with is far harder. Banks follow the written words as authoritative if the two ever disagree.
The convention differs from how you'd normally spell out a number: whole dollars are written in words, but cents are written as a fraction over 100 (e.g. "99/100"), not spelled out — writing "and ninety-nine cents" instead of "and 99/100" is technically non-standard, even though most tellers would still accept it.
Why Use It?
- Produces the exact convention banks expect — cents as a /100 fraction, not spelled out.
- Works for Dollars, Pounds and Euros.
- Optional "Only" suffix — a common practice that closes off the line against tampering.
- Handles amounts up to nearly a trillion, in case you ever need it.
- Free, instant, no account, runs entirely in your browser.
How to Use
- Enter the numeric amount (e.g. 1688.99).
- Choose the currency label (Dollars/Pounds/Euros).
- Optionally check "Append Only" if you want the fraud-prevention convention.
- Copy the result and write it on the amount line of your check.
Example
Input
1688.99Output
One Thousand Six Hundred Eighty-Eight and 99/100 DollarsNote the cents are written as "99/100", not spelled out as "ninety-nine cents" — this is the standard check-writing convention.
Frequently Asked Questions
Why are cents written as a fraction instead of spelled out?
It's the long-standing banking convention — cents as "XX/100" leaves no room for ambiguity or alteration, unlike spelling out "cents" in words. Most banks will still accept spelled-out cents, but the /100 format is what you'll see on pre-printed checks and what tellers expect.
What happens if the numeral amount and the written amount don't match?
Banks treat the written-out amount as authoritative when there's a discrepancy — this is precisely why the words line exists. Double-check both before signing; a mismatch can delay or bounce the check.
Should I add "Only" at the end?
It's a common but optional practice, mainly used to close off empty space at the end of the line so nothing can be added after your amount. Some checkbooks build this into their pre-printed format already; adding it yourself never hurts.
Does this work for currencies other than USD?
The wording convention (amount in words + cents as a fraction) is the same for US Dollars, UK Pounds and Euros — pick the label that matches your check. For other currencies, the spelled-out number itself is still correct English; just substitute your own currency name.
Is my amount sent anywhere?
No. The conversion runs entirely as local JavaScript in your browser — nothing is transmitted, so it's safe to use with real check amounts.