Font Size Converter
RunDev
Convert between px, em, rem, pt, and percentage font sizes. Based on 16px root size.Updated 2026-03-20
The quick brown fox jumps over the lazy dog
Frequently Asked Questions
What is the default base size?
16px is the browser default root font size.
Em vs Rem?
Em is relative to parent element. Rem is relative to root (html) element.
Is this free?
Yes, completely free with no signup.
How to Use
- Select formatting options
- Review output with syntax highlighting
- Check validation messages for issues
- Paste your code or data into the input
FAQ
What browsers are supported?
All modern browsers: Chrome, Firefox, Safari, Edge. Some features need recent versions.
Which standards does it follow?
Follows the latest official specifications — RFC, W3C, or ECMA as applicable.
Can I integrate this into my workflow?
Bookmark for quick access. The URL updates with settings for sharing configurations.
Is the output production-ready?
Yes, generates clean, standards-compliant output suitable for production use.
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