How to Check If a Word or Sentence Is a Palindrome (With Examples)

A palindrome reads the same forwards and backwards. Words like "level", numbers like 12321 and sentences like "A man, a plan, a canal: Panama" all qualify once you ignore spaces and punctuation.

Quick answer

Type a word, number or sentence. The checker removes spaces, punctuation and capital letters, then compares the text with its reverse. Tick strict mode to compare exactly as typed.

Examples

• Words: radar, civic, kayak, madam, rotor, refer
• Numbers: 121, 1331, 12321
• Sentences: "Was it a car or a cat I saw?", "Never odd or even"
• Dates: 02/02/2020 (written 02022020)

How the check works

1. Convert to lower case.
2. Remove everything that is not a letter or digit (normal mode).
3. Reverse the string.
4. Compare with the original.

In strict mode nothing is removed, so "Madam" is not a palindrome (capital M) and "A man, a plan" fails because of spaces and commas.

Steps

1. Open the tool.
2. Type your text.
3. Read the result and the cleaned text that was compared.

Fun facts

• The longest single-word palindrome in English is often given as "tattarrattat" (coined by James Joyce).
• Palindromic numbers appear in puzzles; try finding the next palindromic year.

Teaching use

Great as a coding exercise: write a function that checks palindromes, then handle punctuation and case.