Instantly check if any word, number, or sentence reads the same forwards and backwards.
Type or paste any text below and click Check. The tool will tell you instantly whether it is a palindrome, show you the cleaned string, and visualize each character mirror pair.
Enter multiple words or phrases — one per line — to check all of them at once. Uses the same ignore options selected above.
A palindrome is a word, phrase, number, or sequence of characters that reads the same forwards and backwards. The word comes from the Greek palindromos, meaning "running back again." Simple examples include racecar, level, and madam. Longer palindromic sentences like "A man, a plan, a canal: Panama" remain palindromes when spaces and punctuation are ignored.
In mathematics, palindromic numbers are integers that remain the same when their digits are reversed. In computer science, checking whether a string is a palindrome is a classic algorithm problem used to teach string manipulation, recursion, and two-pointer techniques. Our tool uses the efficient two-pointer approach — comparing characters from both ends simultaneously — which runs in O(n) time and O(1) extra space.