Palindrome Checker Online

What Is a Palindrome Checker?

A palindrome checker determines whether a string reads the same forwards and backwards. Classic word palindromes include racecar, level, and madam. Phrase palindromes like "A man, a plan, a canal: Panama" require ignoring spaces and punctuation. This tool supports both strict (character-exact) and relaxed (ignore case, ignore punctuation) matching modes, and shows a character-by-character visualization of the check.

How to Use Palindrome Checker

1. Type or paste your text into the input field.
2. Toggle Ignore Case or Ignore Spaces & Punctuation as needed.
3. The result updates instantly — green for palindrome, red for non-palindrome.
4. The normalized string and its reverse are shown for clarity.

Features

• Instant check — result updates as you type
• Case-insensitive mode — treats uppercase and lowercase as equal
• Ignore spaces & punctuation — strips non-alphanumeric characters before checking
• Normalized view — shows the processed string and its reverse
• Unicode-aware — works with non-English text
• Privacy-first — runs entirely in your browser

FAQ

What is a palindrome?

A palindrome is a word, phrase, or sequence that reads the same forwards and backwards. Examples include "racecar", "level", and the phrase "A man a plan a canal Panama" (ignoring spaces and punctuation).

Does the checker ignore spaces and punctuation?

Yes, when "Ignore spaces & punctuation" is enabled the checker strips all non-alphanumeric characters before comparing. This lets phrases like "A man, a plan, a canal: Panama" pass as palindromes.

Is the check case-sensitive?

By default the checker is case-insensitive — "Racecar" and "racecar" are treated the same. You can enable case-sensitive mode for strict matching.

Does it work with Unicode and non-English text?

Yes. The checker works with any Unicode text. For case-insensitive matching, JavaScript's built-in toLowerCase() is used, which handles many Latin-script languages.