What is NumbersChecker?

NumbersChecker is a free online toolbox with 139+ utilities for decoding ciphers, solving puzzles, hashing strings, encoding data, number theory, math, text analysis, and science. No login or installation required.

Is NumbersChecker free to use?

Yes, all 139+ tools on NumbersChecker are completely free. No account, subscription, or installation is required.

What cipher tools are available?

NumbersChecker offers 25 cipher tools including Caesar cipher decoder, Vigenère cipher, ROT13, Atbash, Morse code, Base64, Binary, Hex, A1Z26, Rail Fence, Affine, Polybius Square, Scytale, Columnar Transposition, and more.

Can I use NumbersChecker to solve puzzles?

Yes. NumbersChecker includes 12 puzzle tools including a Wordle solver, Hangman solver, Crossword pattern finder, Kakuro clue calculator, Scrabble word builder, substitution cipher solver, and number sequence solver.

Does NumbersChecker have an API?

Yes. Every tool is available as a free JSON REST API. Send a POST request to https://numberschecker.com/api/{toolId} with your input as JSON. No authentication required.

What hashing tools are available?

NumbersChecker provides MD5, SHA-1, SHA-256, SHA-512, and CRC32 hash generators, plus a hash identifier tool that detects the likely algorithm used for any given hash string.

How do I decode a Caesar cipher?

Go to https://numberschecker.com/tool/caesar, enter your ciphertext, and set the shift amount. The tool also shows a brute-force table of all 26 possible shifts so you can spot the correct decoding at a glance.

What number tools are available?

NumbersChecker has 15 number tools including a base converter (binary, octal, hex, and any base 2–36), Roman numeral converter, prime factorization, GCD and LCM calculator, Fibonacci generator, Euler totient, Chinese Remainder Theorem solver, and number-to-words converter.

Text Tools — Free Online Text Utilities

Reverse Text

Reverse a string character by character.

Letter Counter

Count letter/character frequencies in text.

Word Count

Count words, lines, and characters.

Anagram Solver

Find all anagrams of a word or phrase.

Text Case Converter

Convert text between cases (UPPER, lower, Title…).

Sort Lines

Sort lines alphabetically or by length.

Remove Duplicate Lines

Remove duplicate lines from text.

Find & Replace

Find and replace text with regex support.

Text Diff

Show differences between two texts.

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text.

Palindrome Checker

Check if a string is a palindrome.

NATO Phonetic Alphabet

Convert text to NATO phonetic spelling.

Pig Latin

Convert English text to Pig Latin.

Leet Speak (1337)

Translate text to leet speak.

Text Statistics

Readability scores and text statistics.

Regex Tester

Test and debug regular expressions.

Zalgo Text

Add glitchy combining diacritics to text.

Text 180°

Flip text upside down using Unicode.

camelCase ↔ snake_case

Convert between common identifier naming styles.

Word Wrap

Wrap text at a specified column width.

Text Tools — 20 tools

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