Isogram Checker
Check whether a word is an isogram (no repeated letters).
Any repeated letters?
An isogram is a word with no repeating letters — a small linguistic curiosity and a staple of word games. This checker tells you whether your input qualifies and points out any letters that repeat.
“background” is a perfect isogram, while “letter” is not, because t and e each appear twice. The tool lists the offenders and their counts so the reason is clear.
Simple and private
It tallies the letters in your text in your browser, ignoring spaces and case, so nothing you type is uploaded.
Frequently Asked Questions
What is an isogram?
A word or phrase in which no letter appears more than once. “Background” and “uncopyrightable” are well-known examples.
What does the tool report?
Whether the input is an isogram, and if not, which letters repeat and how many times.
Are spaces counted?
No — only letters are checked, so spaces, digits, and punctuation are ignored and case does not matter.
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