What makes a phrase a palindrome?

A palindrome reads identically forwards and backwards once you ignore spaces, punctuation, and letter case. 'A man, a plan, a canal: Panama' is the classic example.

Does the checker ignore spaces and punctuation?

Yes. The checker strips everything except letters and digits and lowercases the result before comparing it to its reverse, which is the standard convention for phrase palindromes.

Are the listed palindromes verified?

Every entry in the built-in list is checked by the same algorithm at runtime, so anything shown to you is a genuine palindrome rather than a near-miss.

What is the longest palindrome?

The list includes longer constructed sentences. In English the longest natural single-word palindrome is often cited as 'tattarrattat', coined by James Joyce, while phrase palindromes can be arbitrarily long.

Does anything get uploaded?

No. Generation and checking both run entirely in your browser with JavaScript, so nothing you type or generate leaves your device.

Palindrome Generator

Palindromes on demand

This tool serves a random palindrome — a word or phrase that reads the same forwards and backwards — from a curated, verified list, and includes a checker so you can test your own. It is handy for word games, puzzle design, and idle linguistic curiosity.

How it works

For checking, the input is normalized: every character that is not a letter or digit is removed and the rest is lowercased. The cleaned string is then compared to its reverse:

clean = text.replace(non-alphanumerics).toLowerCase()
isPalindrome = (clean === reverse(clean))

This is why “A man, a plan, a canal: Panama” counts — once spaces, commas, the colon, and case are stripped, both directions match. The same routine validates every entry in the built-in list at runtime, so you only ever see genuine palindromes.

Example

racecar reverses to racecar — palindrome.
Was it a car or a cat I saw? normalizes to wasitacaroracatisaw, which is its own reverse — palindrome.
hello reverses to olleh — not a palindrome.

Everything runs locally, so your puzzles and drafts stay private.