# String Byte Size Calculator

> Measure text in UTF-8, UTF-16 and UTF-32 bytes, code points and grapheme clusters.

The size of a string depends on the encoding. This tool reports UTF-8, UTF-16 and UTF-32 byte counts alongside JavaScript's string length, the Unicode code point count and the number of grapheme clusters — the last being what a person actually calls a character.

**URL:** https://convertto.tech/t/string-byte-counter
**Category:** Text Tools (https://convertto.tech/c/text-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your text.
2. The result appears immediately — copy or download it.

## FAQ

### Why is my emoji counted as two characters?

JavaScript measures strings in UTF-16 units, and any character above U+FFFF — which includes almost all emoji — needs two of them. Use the grapheme cluster count for the number a person would give.

### Which number does my database column limit use?

Usually UTF-8 bytes. A VARCHAR(255) in MySQL with utf8mb4 holds 255 characters but can consume up to 1,020 bytes, so a byte-limited column fills up sooner than the character count suggests.

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