Convert ASCII to Bytes

An 8-bit unsigned integer between 0 and 255. The tool runs your text through TextEncoder, which produces UTF-8 bytes, and then prints each one in your chosen format.

For protocol analysis, firmware development, test fixtures, debugging encoding issues, generating C/JS array literals, or learning how computers store text at the byte level.

Decimal (0-255), hexadecimal (00-FF), binary (8-bit groups), and octal (000-377). Each has its own default pad width; the zero-pad toggle enforces fixed-width output.

Yes. Encoding runs entirely in your browser – nothing is uploaded, cached, or tracked. After the page loads you can disconnect the network and keep encoding indefinitely.

UTF-8. Plain ASCII (0-127) looks identical in both, but the tool uses TextEncoder so non-ASCII characters correctly expand to their multi-byte UTF-8 form.

Yes. HTML, CSS, and JavaScript are self-contained. Once the page has loaded, you can turn off Wi-Fi and the tool keeps working – useful on air-gapped machines.

Yes, 100% free with no cap on input length or number of encodes. No sign-up, no premium tier, no watermark.

The JSON-array and C-array wrappings are paste-ready literals. JSON ([72, 101, 108]) drops into any JS/TS/Python list. C-array ({ 0x48, 0x65, 0x6C }) fits directly into a uint8_t[] initializer – enable hex format, zero-pad, and the 0x prefix for the cleanest result.

Yes. Emoji encode to 4 UTF-8 bytes – 😀 becomes F0 9F 98 80 in hex. The “multi-byte chars” counter in the stats line tells you how many characters expanded beyond one byte.

Use the sibling Bytes to ASCII converter. Round-trip is exact: the byte array out of this tool pastes cleanly into the other for decoding back to the original string.