Palindrome Checker

Is it a palindrome?

Check whether text reads the same forwards and backwards. A palindrome is a word, number or phrase that is unchanged when reversed — level, racecar, 12321 — and with the matching options you can also catch full phrase palindromes that include spaces and punctuation. Useful for word games, coding puzzles, crosswords and curiosity.

How it works

The checker normalises your text, reverses it, and compares the two. Two optional rules control the normalisation:

if "ignore spaces and punctuation":  keep only letters and numbers (\p{L}, \p{N})
if "ignore case":                    convert to lowercase
result = (cleaned text == reverse of cleaned text) and length > 0

Reversal is Unicode-aware (it splits on code points), so accented and non-Latin characters reverse correctly. With both options on, only the underlying letters and digits are compared, which is what makes long phrase palindromes match.

Example

Input: “A man, a plan, a canal: Panama” with both options enabled.

• Strip non-alphanumerics → amanaplanacanalpanama
• Lowercase → already lowercase
• Reverse → amanaplanacanalpanama
• Cleaned text equals its reverse → Yes, it’s a palindrome

The check runs entirely in your browser — nothing is uploaded.