Binary to Text Converter

How ASCII maps characters to binary

ASCII (American Standard Code for Information Interchange) was published in 1963 and became the foundational character encoding for computing. It assigns a unique 7-bit integer code to each printable character, plus a set of control codes. The letter A is code 65, B is 66, lowercase a is 97, the digit 0 is 48, and a space is 32.

In practice, ASCII values are stored in 8-bit bytes even though the codes only use 7 bits. The leading bit is 0 for standard ASCII characters. So the letter H is decimal 72, which is 01001000 in binary. The letter i is decimal 105, which is 01101001. To decode the binary string 01001000 01101001, you convert each 8-bit group to its decimal value, look up the corresponding ASCII character, and concatenate the results to get the text.

This tool automates that lookup. It reads each space-delimited 8-bit group, converts it to a decimal code point, and outputs the matching character. Non-printable control characters (codes 0-31 and 127) are displayed with a placeholder rather than rendered invisibly.

Decoding binary from network captures

Network analysis tools sometimes display payload bytes as binary strings when you examine individual bits of a packet field. If you captured a plain-text HTTP request and the tool shows it in binary, pasting the payload here lets you read the underlying text without manually converting each byte.

Binary representations also appear in educational contexts - computer science courses and tutorials often express strings as binary to demonstrate how computers store text at the bit level. This converter lets you verify your work: encode a word as binary manually, then paste it here to check that it decodes back to the original string.

Steganography tools and CTF challenges frequently embed hidden messages as binary-encoded text. Being able to quickly paste and decode a binary blob is useful for that kind of analysis.

Expected input format

Each character must be represented as exactly 8 binary digits (bits). Groups should be separated by a single space. The input 01001000 01100101 01101100 01101100 01101111 decodes to the word Hello.

If a group contains fewer or more than 8 bits, or contains characters other than 0 and 1, the tool will flag that group as invalid and skip it, outputting the successfully decoded characters from the rest of the input. This lets you spot formatting errors in a long binary string without losing all context.

Frequently asked questions