🔁 Palindrome Checker
By ToolNimba Editorial Team · Updated 2026-06-19
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Enter some text to check whether it reads the same forwards and backwards.
- Cleaned text:
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- Reversed:
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A palindrome is a word, phrase or number that reads the same forwards and backwards, like "level" or "racecar". This palindrome checker tells you instantly whether your text qualifies. Paste a word or a whole sentence, choose whether to ignore case, spaces and punctuation, and see a clear yes or no plus the cleaned string that was actually compared.
What is the Palindrome Checker?
A palindrome is any sequence of characters that is identical when reversed. "noon" reversed is "noon", so it is a palindrome, while "table" reversed is "elbat", so it is not. The idea applies to single words, full phrases, and even numbers (12321 is a numeric palindrome). The word comes from the Greek palindromos, meaning "running back again".
Whether a phrase counts as a palindrome usually depends on how you normalize it first. The classic example "A man, a plan, a canal, Panama" is only a palindrome once you lowercase the letters and remove the spaces, commas and capital letters. Read literally, character for character, it is not symmetric. That is why this tool gives you three toggles: ignore case, ignore punctuation and ignore spaces. With all three on, you are testing the letters and digits alone, which is the most common definition of a phrase palindrome.
Under the hood the check is simple: the tool builds a cleaned version of your text according to the options you chose, reverses that cleaned string, and compares the two. If they match exactly, the text is a palindrome. The reversal works on whole Unicode characters, so accented letters and emoji are not broken apart. Everything happens in your browser, so nothing you type is sent anywhere.
When to use it
- Checking a single word like "rotator" or "deified" for a crossword, puzzle or spelling game.
- Testing a full phrase such as "Was it a car or a cat I saw?" after ignoring case and punctuation.
- Verifying numeric palindromes (for example 12321 or a date) for a maths exercise or programming test.
- Confirming the expected output while writing or debugging a palindrome function in a coding interview.
How to use the Palindrome Checker
- Type or paste your word, phrase or number into the text box.
- Decide whether to ignore case, punctuation and spaces using the three checkboxes (all on by default).
- Read the verdict: yes or no, with a short explanation.
- Check the cleaned text and its reverse below to see exactly what was compared.
Formula & method
Worked examples
Checking the phrase "A man, a plan, a canal, Panama" with ignore case, spaces and punctuation all on.
- Lowercase the text: a man, a plan, a canal, panama
- Remove spaces and punctuation: amanaplanacanalpanama
- Reverse the cleaned text: amanaplanacanalpanama
- Compare: the cleaned text equals its reverse
Result: Yes, it is a palindrome
Checking the word "Hello" with default options.
- Lowercase the text: hello
- No spaces or punctuation to remove: hello
- Reverse the cleaned text: olleh
- Compare: hello does not equal olleh
Result: No, it is not a palindrome
Examples of palindromes and non-palindromes
| Text | Type | Palindrome? |
|---|---|---|
| racecar | single word | Yes |
| level | single word | Yes |
| Was it a car or a cat I saw? | phrase (ignore case and punctuation) | Yes |
| 12321 | number | Yes |
| palindrome | single word | No |
| hello world | phrase | No |
Common mistakes to avoid
- Forgetting to ignore case on phrases. With case sensitivity on, "Madam" fails because the capital M does not match the trailing lowercase m. Turn on ignore case to test it as a true word palindrome.
- Leaving spaces and punctuation in a phrase test. Phrase palindromes like "Never odd or even" only work once spaces are removed. If you keep spaces and punctuation, most famous examples will be reported as not palindromes.
- Assuming every word that looks symmetric is a palindrome. It is easy to misjudge longer words by eye. The tool compares the cleaned string to its exact reverse, so trust the verdict over a quick glance.
- Confusing a palindrome with an anagram. A palindrome reads the same backwards. An anagram simply rearranges the same letters into another word. They are different ideas, this tool checks only for palindromes.
Glossary
- Palindrome
- A word, phrase or number that reads the same forwards and backwards after any chosen normalization.
- Normalization
- Cleaning the text before comparison, for example lowercasing it and removing spaces and punctuation.
- Reverse
- The same characters written in the opposite order. "abc" reversed is "cba".
- Alphanumeric
- Characters that are either letters or digits, with no spaces or symbols.
- Numeric palindrome
- A number whose digits read the same in both directions, such as 1331 or 90909.
Frequently asked questions
What is a palindrome?
A palindrome is a word, phrase or number that reads the same forwards and backwards. "level", "racecar" and 12321 are all palindromes. For phrases, you usually ignore case, spaces and punctuation first, which is why this tool lets you toggle those options.
Is "A man, a plan, a canal, Panama" a palindrome?
Yes, once you lowercase it and remove the spaces and punctuation. The cleaned letters spell "amanaplanacanalpanama", which is identical when reversed. With the ignore case, spaces and punctuation options on, this tool reports it as a palindrome.
Does case matter when checking a palindrome?
It depends on the option you choose. With ignore case on (the default), "Madam" is treated as a palindrome. With ignore case off, the capital M will not match the lowercase m, so the same word is reported as not a palindrome.
Can numbers be palindromes?
Yes. A numeric palindrome has digits that read the same in both directions, such as 121, 1331 or 90909. Just type the number into the box and the checker compares it to its reverse like any other text.
Does the spaces and punctuation toggle change the result?
Often, yes. Many famous palindromes are sentences that only work once spaces and punctuation are stripped out. If you turn those options off, the tool compares every character literally, including spaces and commas.
Is my text sent to a server?
No. The palindrome check runs entirely in your browser using plain JavaScript. Nothing you type is uploaded, stored or sent anywhere, so you can safely paste private or sensitive text.