What is a palindrome?

A palindrome is a word, phrase, number, or sequence that reads the same forwards and backwards. Classic examples include "racecar", "level", and the phrase "A man, a plan, a canal: Panama". The term comes from the Greek words "palin" (again) and "dromos" (direction or way).

What is the longest palindrome word in English?

One of the longest single-word palindromes in English is "tattarrattat", coined by James Joyce in Ulysses (1922) to represent a knock on a door — it has 12 letters. Among real dictionary words, "detartrated" (11 letters, a chemistry term) is often cited as one of the longest.

Is a single letter a palindrome?

Yes. By convention, a single character reads the same forwards and backwards, so it satisfies the palindrome definition. Similarly, an empty string is considered a palindrome in most formal definitions.

Why does "A man, a plan, a canal: Panama" count as a palindrome?

When you remove all spaces and punctuation and convert to lowercase, the phrase becomes "amanaplanacanalpanama", which reads identically forwards and backwards. The checker's "Ignore Spaces", "Ignore Punctuation", and "Ignore Case" options handle this automatically.

What is the 196 algorithm (Lychrel process)?

The Lychrel process repeatedly adds a number to its digit-reversal. For most numbers, this quickly produces a palindrome. For example, 57 + 75 = 132, then 132 + 231 = 363 — a palindrome in 2 steps. The number 196 is the most famous candidate that may never reach a palindrome, hence the "196 algorithm" name.

Does this tool handle non-English or accented characters?

Yes. With the "Unicode Aware" option enabled, the tool uses a Unicode-aware regex (/[^\p{L}\p{N}]/gu) to strip punctuation, correctly handling letters from any language, accented characters, and non-ASCII digits.

Is my text sent to a server?

No. All palindrome checking, generation, and quiz logic runs entirely in your browser using JavaScript. Nothing you type is ever transmitted to a server.

Can numbers be palindromes?

Yes. A number is a palindrome when its digit string reads the same forwards and backwards — for example 121, 12321, or 1001001. The Palindrome Generator's Number mode can also show you how many reverse-and-add steps any number needs to reach a palindrome.

Palindrome Checker

Check palindromes, explore famous examples, and generate number palindromes

Updated Mar 2026100% Private — runs in browser

Palindrome Checker

Type a word, phrase, or number to check instantly.

Ignore spaces
"race car" = "racecar"Ignore punctuation
"A man, a plan..." worksIgnore case
"Racecar" = palindromeUnicode aware
Handle non-ASCII chars

Start typing to see the palindrome analysis

Famous Palindromes

Click any example to load it into the checker.

Palindrome Generator

Discover palindrome words or generate number palindromes step-by-step.

Palindrome Quiz

Test your knowledge — palindrome or not?

5 random words will appear one by one. Decide if each is a palindrome!

How to Use Palindrome Checker

1
Type or paste any word, phrase, or number into the large input field in the Palindrome Checker section.
2
Toggle the options (Ignore Spaces, Ignore Punctuation, Ignore Case, Unicode Aware) to control how the check is performed.
3
Watch the result update live — a green badge confirms a palindrome and a red badge shows it is not.
4
Examine the visual character display to see which character pairs mirror each other, highlighted in matching colours.
5
Browse the Famous Palindromes section and use the filter chips (All, Words, Phrases, Numbers) to explore by category.
6
Click any famous palindrome card to instantly load it into the checker and see its analysis.
7
Open the Palindrome Generator, switch to Number mode, enter any number, and view the step-by-step reverse-and-add process to reach a palindrome.
8
Test your knowledge in the Palindrome Quiz — answer Palindrome or Not Palindrome for 5 random items and see your final score.

About Palindrome Checker

Free palindrome checker — instantly check if any word, number, phrase, or sentence is a palindrome. Supports case-insensitive checking, ignore spaces and punctuation options, and shows the reversed text for comparison.

Key Features

Word & Phrase Check: Check single words, numbers, or entire sentences.
Flexible Options: Toggle case sensitivity, ignore spaces, and ignore punctuation.
Reversed Display: See the reversed version of your input for visual comparison.
Batch Check: Check multiple words at once, one per line.
Fun Examples: Pre-loaded famous palindromes to explore and learn.

Who Is This For?

Students learning about palindromes, word game enthusiasts, programmers testing string logic, teachers creating classroom activities, and anyone curious about language patterns.

Privacy & Security

Runs 100% in your browser — no signup, no uploads, no data stored.

Palindrome Checker

Palindrome Checker

Famous Palindromes

Palindrome Generator

Palindrome Quiz

How to Use Palindrome Checker

About Palindrome Checker

Key Features

Who Is This For?

Privacy & Security

Frequently Asked Questions about Palindrome Checker

What is a palindrome?

What is the longest palindrome word in English?

Is a single letter a palindrome?

Why does "A man, a plan, a canal: Panama" count as a palindrome?

What is the 196 algorithm (Lychrel process)?

Does this tool handle non-English or accented characters?

Is my text sent to a server?

Can numbers be palindromes?

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