Text to ASCII binary

Convert text to its ASCII binary representation and vice-versa.

Enable JavaScript to use the interactive tool. The guide below explains how it works.

Text to Binary

What it does

This tool converts plain text into its binary representation, one 8-bit group per character, and converts binary back into readable text. Both directions live on the same page so you can check a round trip.

Why someone uses it

• Learning how computers store characters as numbers and bits.
• Solving puzzles, CTF challenges and geocaching clues that hide messages in binary.
• Producing binary strings for teaching materials or documentation.
• Decoding a stray string of 0s and 1s back into words.

Step-by-step instructions

1. Text to binary: type or paste text into the first card. The binary appears below it. Use Copy binary to clipboard to copy it.
2. Binary to text: paste groups of 8 bits (spaces between groups are fine) into the second card. The decoded text appears below.
3. If the binary card shows a validation error, check that the total number of bits is a multiple of 8.

Examples

• Hi → 01001000 01101001
• A → 01000001
• 01001000 01100101 01101100 01101100 01101111 → Hello
• 123 → 00110001 00110010 00110011 (the characters "1", "2", "3", not the number 123).

Understanding the results

Each character is looked up in the ASCII table and written as an 8-bit binary number. Uppercase "A" is decimal 65, which is 01000001 in binary; lowercase "a" is 97, 01100001. The two differ by a single bit (the third from the left), which is why case is easy to flip in low-level code. Bits are read from left (most significant) to right (least significant). When decoding, each 8-bit group is converted back to its decimal value and then to the matching character.

FAQs

• Does it support emoji or accented letters? It is designed for ASCII text. Characters outside the ASCII range will not round-trip the way plain letters do.
• Do the spaces between bytes matter? They are for readability; the decoder needs the total bit count to be a multiple of 8.
• Is binary a form of encryption? No. It is just another way of writing the same data, and anyone can decode it.
• Is my text sent anywhere? No, conversion runs in your browser.

Common mistakes

• Dropping a leading zero. 1001000 is 7 bits; the full byte is 01001000.
• Mixing up converting a number to binary with converting the text of that number.
• Pasting binary with extra characters (commas, letters) and getting a validation error.

Use cases

• Computer science classes covering data representation.
• Capture-the-flag and puzzle solving.
• Debugging low-level protocols where you inspect raw bits.
• Creating novelty messages in binary.

Related tools

• Integer Base Converter: Convert numbers between binary, decimal, hex and more.
• Text to Unicode: Get numeric character codes for text.
• Base64 String Converter: A more compact text-safe encoding for binary data.