PX to REM Converter
Convert pixels to REM or REM to pixels instantly using the standard 16px base size or your own custom root font size.
CSS Unit Converter
Enter a value below. Your result updates automatically.
Most browsers use a default root size of 16px.
Choose how many digits to display after the decimal.
Formula: pixels ÷ 16 = rem
Quick pixel values
Why Use This PX to REM Calculator?
Built for developers, designers and anyone creating responsive CSS layouts.
Instant Results
Values are converted automatically while you type, without reloading the page.
Custom Base Size
Use the standard 16px root size or enter the font size used by your own CSS project.
Flexible Precision
Control the number of decimal places to create cleaner and more accurate CSS values.
PX and REM Conversion Formulas
Use these simple formulas when converting CSS units manually.
Pixels to REM
REM = Pixels ÷ Root Font Size
Example: 32px ÷ 16px = 2rem.
REM to Pixels
Pixels = REM × Root Font Size
Example: 2rem × 16px = 32px.
PX to REM Conversion Chart
Common CSS values calculated using a 16px root font size.
| Pixels | REM | CSS Example | Action |
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Free Online PX to REM Converter
The MegaToolsHub PX to REM Converter helps web developers and designers convert CSS pixel values into scalable REM units. It also supports reverse conversion from REM to pixels, making it useful when checking or updating responsive website designs.
You can enter any pixel or REM value, select the required decimal precision and change the root font size according to your project. The calculation takes place directly in your browser and the result is displayed instantly.
What Is a Pixel in CSS?
A pixel, written as px, is an absolute CSS unit commonly used for font sizes, spacing, borders, icons and other interface elements. Pixel measurements are easy to understand, but fixed values may not always scale well with a user's accessibility or browser font settings.
What Is REM in CSS?
REM means root em. A REM value is calculated relative to the font size of the root HTML element. When the root font size is 16px, 1rem equals 16px, 2rem equals 32px and 0.5rem equals 8px.
Why Convert PX to REM?
REM units can make typography and spacing more flexible across desktop, tablet and mobile devices. They also respect changes to root font settings, which can help improve accessibility and make a design system easier to maintain.
- Create scalable typography and spacing.
- Improve consistency across responsive layouts.
- Support browser font-size preferences.
- Maintain a reusable CSS sizing system.
- Quickly convert values from design files into CSS.
How to Use the Converter
Choose PX to REM or REM to PX, enter your value and confirm the root font size. The converted value appears immediately. You can then copy the result and paste it into your CSS, SCSS, website builder or design documentation.
font-size applied to your HTML element when exact
project-specific conversion is required.
Frequently Asked Questions
Helpful answers about pixels, REM units and CSS conversions.
Divide the pixel value by the root font size. For example, when the root size is 16px, 32px divided by 16 equals 2rem.
Multiply the REM value by the root font size. For example, when the root size is 16px, 1.5rem multiplied by 16 equals 24px.
No. It usually equals 16px because that is the common browser default, but it changes when a different font size is applied to the root HTML element.
REM is often preferred for scalable typography and spacing, while pixels can still be useful for elements that require a fixed measurement. Many projects use a combination of both.
No. The conversion is performed locally in your browser and the entered values are not uploaded by the calculator.