ASCII & UTF-8 Converter
Characters and bytes are not the same count.
Characters and bytes are not the same count. Character codes in decimal, hex, octal and binary, with the UTF-8 byte count alongside the character count.
Up to 200 characters.
Decimal codes
72 101 108 108 111
5 characters · 5 UTF-8 bytes · all ASCII
Character count and byte count are the same only for pure ASCII. An emoji is one character and four UTF-8 bytes; an accented Latin letter is one character and two, which is why a database column limited to 255 bytes does not hold 255 characters. ASCII covers 0 to 127 and UTF-8 was designed to extend it without breaking it: every ASCII byte means the same thing in UTF-8, which is why the encoding took over. Bytes above 127 signal a multi-byte sequence. The gap between character length and byte length causes real bugs — truncating a string at a byte boundary can split a multi-byte character in half and produce invalid text, which is why length limits should be counted in whatever unit the storage actually uses.
How the ASCII & UTF-8 Converter works
Character codes in decimal, hex, octal and binary, with the UTF-8 byte count alongside the character count. The two differ the moment anything outside ASCII appears.
Also known as: text to binary converter · character to ascii code · how many bytes is an emoji · utf 8 byte counter
Where to go next
The ASCII & UTF-8 Converter question rarely arrives on its own. These are the ones that usually come with it:
- Colour Converter — With the WCAG contrast that decides readability.
- Password Entropy Calculator — No 'strong' verdict — a verdict needs a threat model.
- Speed Distance Time Calculator — Any one of the three from the other two, in four units.
- Acceleration Calculator — Acceleration in m/s² and in g, which is the legible one.
Frequently asked questions
What is ASCII?
A 7-bit encoding covering 0 to 127 — the English alphabet, digits, punctuation and control codes. Everything else needs a wider encoding.
Why are bytes and characters different?
UTF-8 uses one byte for ASCII, two or three for most other scripts, and four for emoji. One emoji is one character and four bytes, which is why a 255-byte column does not hold 255 characters.
Why did UTF-8 win?
Because it extends ASCII without breaking it. Every ASCII byte means the same thing in UTF-8, so existing text and existing software kept working — which no other Unicode encoding managed.
What happens if I truncate at a byte boundary?
You can split a multi-byte character in half and produce invalid text, usually shown as a replacement character. Length limits should count in whatever unit the storage actually uses.
What are the codes below 32?
Control characters — newline is 10, carriage return 13, tab 9, null 0. They date from teleprinters and several are still load-bearing in modern protocols.
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Open