---
title: "PX・Rem Calculator - Convert px and rem at your base size | Web ToolBox"
description: "Convert between px and rem based on a base font size. Enter either value and the other updates automatically, which helps when moving between fixed and relative units in CSS font sizes and spacing."
canonical_url: "https://web-toolbox.dev/en/tools/px-rem-calculator"
meta:
  author: K
  "og:description": "Convert between px and rem based on a base font size. Enter either value and the other updates automatically, which helps when moving between fixed and relative units in CSS font sizes and spacing."
  "og:image": "https://web-toolbox.dev/og/en/tools/px-rem-calculator-f38b58ef.png"
  "og:image:alt": "PX・Rem Calculator"
  "og:image:height": "630"
  "og:image:width": "1200"
  "og:title": "PX・Rem Calculator - Convert px and rem at your base size | Web ToolBox"
---

> Index of every page on this site: [llms.txt](https://web-toolbox.dev/llms.txt)

# **PX・Rem Calculator**

Convert px and rem both ways

**Base Font Size (px)**

**px value**

**rem value**

Editing either value updates the other

24 ÷ 16 = 1.5rem

## **Common Values**

16px base

<dl>

<dt>1px</dt>
<dd>**0.0625rem**</dd>

<dt>2px</dt>
<dd>**0.125rem**</dd>

<dt>4px</dt>
<dd>**0.25rem**</dd>

<dt>8px</dt>
<dd>**0.5rem**</dd>

<dt>10px</dt>
<dd>**0.625rem**</dd>

<dt>12px</dt>
<dd>**0.75rem**</dd>

<dt>14px</dt>
<dd>**0.875rem**</dd>

<dt>16px</dt>
<dd>**1rem**</dd>

<dt>18px</dt>
<dd>**1.125rem**</dd>

<dt>20px</dt>
<dd>**1.25rem**</dd>

<dt>24px</dt>
<dd>**1.5rem**</dd>

<dt>32px</dt>
<dd>**2rem**</dd>

<dt>40px</dt>
<dd>**2.5rem**</dd>

<dt>48px</dt>
<dd>**3rem**</dd>

<dt>64px</dt>
<dd>**4rem**</dd>

<dt>96px</dt>
<dd>**6rem**</dd>

</dl>

## What is PX・Rem Calculator?

PX・Rem Calculator converts between px and rem based on a base font size. You can see what `**24px**` is in rem and what `**1.5rem**` is in pixels on the same screen.

Use it when moving CSS font sizes and spacing from fixed pixels to rem, or when checking what a rem value means in pixels.

## How to Use

1. Enter a base font size or pick one of the common sizes.
2. Enter a value in either PX or REM.
3. Check the other value and the formula, then copy the result.

Changing the base font size recalculates the value you edited last into the other unit.

## Main Settings

### Base Font Size

The value used as the basis for 1rem. The browser default is `**16px**`. If your project sets a different font size on `**html**`, match that value here.

### PX and REM Values

Editing either value updates the other. With a base size of `**16px**`, entering `**24px**` shows `**1.5rem**`.

## Common Values

A list of common pixel values with their rem equivalents. Changing the base font size updates the rem column. Use the copy icon on each row to copy the rem value.

## Use Cases

- Replacing pixel values from a design file with CSS rem values
- Checking what a rem value in existing CSS means in pixels
- Seeing how sizes change when the root font size changes

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