64px → REM

64px to REM - 4rem at 16px Base

At the default browser root size of 16px, 64px equals 4rem. Formula: rem = px ÷ 16.

Last reviewed: June 28, 2026

CSS snippet

.example {
  font-size: 4rem; /* 64px at 16px root */
  padding: 4rem;
}

PX to REM formula

rem = px ÷ root font size

64px ÷ 16px = 4rem

Worked example: To convert 64px at a 16px root, divide 64 by 16. 64 ÷ 16 = 4. Write font-size: 4rem; instead of font-size: 64px; so text scales when users enlarge their browser default font size.

Common use cases at 64px (4rem)

Category	Tailwind / design use	CSS property example
Font size	text-6xl / display headings	`font-size: 4rem;`
Spacing	p-16	`padding: 4rem;`
Gap / margin	p-16	`gap: 4rem;`

  
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  64px
 
 
  
Also see  50px to rem

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 64px to REM FAQ
How do you convert 64px to rem?
Divide 64 by the root font size. At the default 16px base: 64 ÷ 16 = 4rem. Formula: rem = px ÷ root font size. Paste font-size: 4rem; into your CSS so typography scales when users change their browser default font size.
What is 64px in rem at 16px base?
At a 16px root font size, 64px equals exactly 4rem. This is the browser default unless your project or the user changes html { font-size }. If your root differs, scale with rem = 64 ÷ yourRootPx before shipping production styles.
Should I use 4rem or 64px in CSS?
Use 4rem for typography and spacing that should scale with the user's root font-size preference - important for accessibility. Reserve 64px for fixed values like 1px borders or bitmap image dimensions. Prefer rem for layout rhythm so zoom and OS font settings do not clip text.
How do I convert 4rem back to pixels?
Multiply 4rem by 16: 4 × 16 = 64px. Reverse formula: px = rem × root font size. Use that when a design tool exports rem tokens and you need pixel sizes for image assets, canvas drawing, or developer handoff docs.
Where is 64px commonly used in web design?
64px (4rem) maps to text-6xl / display headings in typical design systems. For Tailwind spacing, see p-16. Check the use-case table on this page for CSS property examples covering font-size, padding, and gap so you can pick a consistent token across components and breakpoints.
    Full converter
 
PX to REM Converter - any value, custom base
  
   Cheat sheet
 
PX to REM cheat sheet - 12px through 64px