Text Byte Size Calculator
Find the real UTF-8 byte size of any text, not just its character count.
How to Check Text Byte Size
- Type or paste your text.
- See its character count alongside its real UTF-8 byte size, updated instantly.
Frequently Asked Questions
Why is byte size different from character count?
In UTF-8, plain English letters and basic punctuation each take exactly 1 byte, but accented letters, most non-Latin scripts, and symbols often take 2 or 3 bytes, and emoji typically take 4 bytes. So a string can have far more bytes than characters once it includes anything beyond basic ASCII text.
Why does this matter for real use cases?
Many systems enforce limits in bytes, not characters — database column sizes, API request/response payload caps, and some legacy SMS or messaging limits all commonly count bytes. A string that looks short in character count can still exceed a byte-based limit if it uses multi-byte characters.
Does this count the byte order mark (BOM) or line ending style?
No — it measures only the exact text you typed, encoded as UTF-8, with no BOM added and no line-ending conversion. If a file you're comparing against adds a BOM or uses different line endings (like CRLF vs LF), its actual byte size on disk may differ slightly from what's shown here.
Is my data sent anywhere?
No — the calculation happens entirely in your browser using JavaScript, so nothing you type is ever sent to a server.