Palindrome Checker
This palindrome checker tells you in one step whether a word, phrase or number reads the same forwards and backwards. If it does not, you see the first position where it breaks and the longest palindromic stretch hidden in your text.
Source: Unicode Standard Annex #29 – Text Segmentation (grapheme clusters: one visible character = one position). Updated: .
How it is calculated
A palindrome is a word, number or phrase that stays the same when read backwards. Familiar examples are level, racecar, “Madam, I’m Adam” and the number 12321. For whole sentences the rule normally applies after removing spaces, punctuation and capital letters.
How the check works
- The text is first cleaned according to your options: upper and lower case are treated alike, spaces and punctuation are dropped, accented letters are reduced to the plain letter.
- Then the first character is compared with the last, the second with the second to last, and so on up to the middle. Each match is one mirror pair.
- If a pair does not match, the tool names the first mismatch, so you can see where a sentence that “almost works” falls apart.
- The longest palindromic stretch is found even in texts that are not palindromes: “Hello Otto” contains “otto”.
Letter palindromes and word palindromes
Besides the letter palindrome there is the word palindrome, where the order of the words is mirrored, as in “you bet, bet you”. The tool shows this extra check as soon as your text has at least two words. If you only want to flip a text around, use reverse text; related letter games are at the anagram solver.
Frequently asked questions
What is a palindrome?
A palindrome is a sequence of characters that reads the same forwards and backwards, such as “noon”, “kayak” or the number 4554. For sentences, spaces, punctuation and capitalization are usually ignored.
Does capitalization matter?
By the usual rule it does not: “Anna” is a palindrome. For a strict test, switch the option off – then “Anna” fails because of the A and the a.
Can numbers be palindromes?
Yes. Numbers like 121, 1331 or 12321 read the same in both directions. Dates such as 02/02/2020 work when you ignore punctuation: 02022020.
How does the tool treat accented letters?
If you wish, as their plain letters: é becomes e, ü becomes u and ß becomes ss. Without that option every character counts exactly as typed.
What is a word palindrome?
There the order of the words is mirrored rather than the letters, for example “hello world hello”. The tool shows this extra check once your text has at least two words.
Sources and legal basis
- Unicode Standard Annex #29 – Text Segmentation (grapheme clusters: one visible character = one position)
- Unicode Standard Annex #15 – Normalization Forms (Akzente trennen)
As of: · Editorial policy
Related tools
- Reverse textReverse text online: write letters backwards, reverse the order of words or lines, or flip text upside down – with a palindrome check, right in your browser.
- Anagram solver: anagrams of a word or of two wordsFree anagram solver: enter letters and see every word made from exactly those letters, common words first. Also two-word anagrams and ? as a wildcard.
- Word unscrambler: make words from lettersUnscramble letters into words instantly: type your letters and get every English word they make, longest first, with Scrabble points. Use ? as a blank tile.
- Word Counter and Character CounterCharacter counter: characters with and without spaces, words, sentences, reading and speaking time, top words – live, with limits for X, Instagram and SMS.
- Password GeneratorGenerate secure random passwords and memorable passphrases with entropy shown in bits — calculated right in your browser, nothing sent or stored.
- Pig Latin translatorPig Latin translator: turn any text into Pig Latin instantly, keeping capitals, punctuation and vowel starts, with your choice of ending. Runs in your browser.
- Online teleprompterFree online teleprompter: paste your script, set the speaking pace, go fullscreen and mirror the text for glass prompters. Keyboard control, text stays local.
- ASCII art generatorCreate ASCII art: turn text into big lettering made of characters or convert a photo to ASCII – with width, character set and contrast. Copy or save as .txt.
- Password Strength CheckerHow secure is my password? Check strength, entropy in bits, and how long it would take to crack — locally in your browser, never sent or stored.