# Charset
> Use when reviewing templates, rendered HTML, or shared components related to Declare UTF-8 character encoding. Validate the final browser-facing markup, not just the source framework abstraction.
- Skill: `thedaviddias/charset` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add thedaviddias/charset`
- Raw SKILL.md: https://api.skillmd.com/api/skills/thedaviddias/charset/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: thedaviddias (https://skillmd.com/u/thedaviddias)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/thedaviddias/charset
---
# Declare UTF-8 character encoding
Missing or incorrect charset causes mojibake (garbled text), broken special characters, and security vulnerabilities from character encoding attacks.
## Quick Reference
- Add `` as the first element in
- Must appear within the first 1024 bytes of the document
- UTF-8 supports all languages and special characters
## Check
Verify that this HTML document declares UTF-8 character encoding in the head section and that it's positioned early in the document.
## Fix
Add as the first meta tag in the head section of the HTML document.
## Explain
Explain why UTF-8 character encoding is essential for international content support and preventing character display issues.
## Code Review
Review templates, server-rendered HTML, and shared components that output markup related to Declare UTF-8 character encoding. Flag exact elements, attributes, and routes where the rendered HTML violates the rule.
---
For full implementation details, code examples, and framework-specific guidance,
see `references/rule.md`.
Rule page: https://frontendchecklist.io/en/rules/html/charset