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Free REM to PX Converter | Katalon Online Tools

The REM to PX converter converts rem values into px units to help developers build scalable, accessible typography and layouts

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Rem to Px Converter

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Blog / Free Tools Numbers Math Units & Code Systems /
Free REM to PX Converter | Katalon Online Tools

Free REM to PX Converter | Katalon Online Tools

Vincent N.
Vincent N.
QA Consultant Updated on

EM

 Pixel REM Percent Point
0.0625em 1px 0.0625rem 6.25% 0.75pt
0.125em 2px 0.125rem 12.5% 1.5pt
0.1875em 3px 0.1875rem 18.75% 2.25pt
0.25em 4px 0.25rem 25% 3pt
0.3125em 5px 0.3125rem 31.25% 3.75pt
0.375em 6px 0.375rem 37.5% 4.5pt
0.4375em 7px 0.4375rem 43.75% 5.25pt
0.5em 8px 0.5rem 50% 6pt
0.5625em 9px 0.5625rem 56.25% 6.75pt
0.625em 10px 0.625rem 62.5% 7.5pt
0.6875em 11px 0.6875rem 68.75% 8.25pt
0.75em 12px 0.75rem 75% 9pt
0.8125em 13px 0.8125rem 81.25% 9.75pt
0.875em 14px 0.875rem 87.5% 10.50pt
0.9375em 15px 0.9375rem 93.75% 11.25pt
1em 16px 1rem 100% 12pt
1.0625em 17px 1.0625rem 106.25% 12.75pt
1.125em 18px 1.125rem 112.5% 13.5pt
1.1875em 19px 1.1875rem 118.75% 14.25pt
1.25em 20px 1.25rem 125% 15pt
1.3125em 21px 1.3125rem 131.25% 15.75pt
1.375em 22px 1.375rem 137.5% 16.50pt
1.4375em 23px 1.4375rem 143.75% 17.25pt
1.5em 24px 1.5rem 150% 18pt
1.5625em 25px 1.5625rem 156.25% 18.75pt
1.625em 26px 1.625rem 162.5% 19.5pt
1.6875em 27px 1.6875rem 168.75% 20.25pt
1.75em 28px 1.75rem 175% 21pt
1.8125em 29px 1.8125rem 181.25% 21.75pt
1.875em 30px 1.875rem 187.5% 22.5pt
1.9375em 31px 1.9375rem 193.75% 23.25pt
2em 32px 2rem 200% 24pt
2.0625em 33px 2.0625rem 206.25% 24.75pt
2.125em 34px 2.125rem 212.5% 25.5pt
2.1875em 35px 2.1875rem 218.75% 26.25pt
2.25em 36px 2.25rem 225% 27pt
2.3125em 37px 2.3125rem 231.25% 27.75pt
2.375em 38px 2.375rem 237.5% 28.5pt
2.4375em 39px 2.4375rem 243.75% 29.25pt
2.5em 40px 2.5rem 250% 30pt
2.5625em 41px 2.5625rem 256.25% 30.75pt
2.625em 42px 2.625rem 262.5% 31.5pt
2.6875em 43px 2.6875rem 268.75% 32.25pt
2.75em 44px 2.75rem 275% 33pt
2.8125em 45px 2.8125rem 281.25% 33.75pt
2.875em 46px 2.875rem 287.5% 34.5pt
2.9375em 47px 2.9375rem 293.75% 35.25pt
3em 48px 3rem 300% 36pt
3.0625em 49px 3.0625rem 306.25% 36.75pt
3.125em 50px 3.125rem 312.5% 37.5pt

What Is a REM to PX Converter?

A REM to PX converter is a specialized utility that helps web developers and designers convert relative rem (root em) units into absolute pixel (px) values. This type of conversion is particularly useful when fine-tuning layouts, ensuring visual precision, or maintaining consistent sizing across various devices and browsers.

In Cascading Style Sheets (CSS), REM units scale relative to the root font size (usually defined on the <html> element). A REM to PX converter calculates the equivalent pixel value by multiplying the rem value by the root font size. For example, if 1rem = 16px, then 2rem equals 32px. This tool simplifies that calculation process, helping developers quickly determine pixel equivalents without manual math.

While REM units are ideal for scalability and accessibility, there are cases where pixel precision is necessary — such as when aligning graphical elements or defining static spacing in fixed layouts. A REM to PX converter bridges that gap, ensuring you can easily switch between flexible and fixed measurement systems depending on your design needs.

What can you do with a REM to PX converter tool?

  • Convert Relative REM Values to Exact Pixel Sizes: Quickly translate rem-based measurements (e.g., 1.25rem) into their pixel equivalents based on the root font size. This is especially helpful for ensuring exact dimensions in icons, containers, or design systems that require precision.

  • Validate Responsive Designs: Check how elements defined in rems appear at different root font sizes, ensuring consistent scaling and alignment.

  • Optimize Accessibility Testing: Understand how changing the root font size affects pixel rendering, helping test accessibility scenarios for users who adjust browser zoom or font settings.

  • Maintain Visual Consistency: When collaborating across design and development teams, pixel conversion helps match mockup dimensions to rem-based implementation.

  • Cross-Platform Compatibility: Works seamlessly across all browsers and operating systems, including Chrome, Safari, Firefox, Edge, Windows, macOS, and Linux.

How to use a REM to PX converter?

  1. Identify the Root Font Size: In most browsers, the default root font size is 16px unless overridden in CSS.

  2. Collect REM Values: Choose the rem-based sizes (e.g., font-size, margin, padding) you want to convert.

  3. Input Values into the Converter: Enter both the rem value and the root font size into the converter.

  4. Get the Pixel Output: The tool will instantly return the equivalent pixel value. For example, 1.5rem with a root font size of 16px equals 24px.

  5. Apply or Reference the Value: Use the pixel results to align design specifications or verify responsive scaling accuracy.

  6. Test Responsiveness: Ensure that scaling remains appropriate across multiple viewports and zoom levels.

Why use PX instead of REM?

  • PX (Pixels): A fixed, absolute measurement unit. Perfect for static elements, icons, and precise design requirements. 16px always equals 16 pixels on screen, regardless of the root font size.

  • REM (Root EM): A relative unit that adapts to the root font size. Ideal for responsive design and accessibility since elements scale proportionally.

For example:

  • With a root font size of 16px, 1rem = 16px and 2rem = 32px.

  • If the root size increases to 20px, 1rem = 20px, and 2rem = 40px.

Conclusion: Use REM for flexibility and accessibility; use PX for pixel-perfect precision. Both have their place: REM for dynamic design systems and PX for exact layout control.

Benefits of Using a REM to PX Converter

  • Simplifies Conversion: Instantly calculates pixel equivalents for rem values without manual math.

  • Ensures Visual Accuracy: Helpful when matching design specs or debugging spacing issues.

  • Improves Design Consistency: Keeps pixel-based mockups aligned with rem-based CSS code.

  • Saves Development Time: Automates repetitive conversions during design implementation.

  • Enhances Accessibility Testing: Makes it easier to simulate font scaling behavior.

  • Responsive Typography Validation: Ensures that rem-defined fonts and spacing behave predictably at different base font sizes.

  • Cross-Browser Consistency: Provides predictable pixel results across all browsers and display types.

Frequently Asked Questions

Which is better, REM or PX?
Use REM for accessibility and responsive scaling. Use PX for exact sizing where flexibility is unnecessary.

How big is 1rem in PX?
By default, if the root font size is 16px, then 1rem = 16px. If the root font size changes, the equivalent pixel value adjusts automatically.

What is 2rem in PX?
With a base font size of 16px, 2rem = 32px. If the root font size is 20px, 2rem = 40px.

Is 16px equal to 1rem?
Yes, when the root font size is 16px. If you increase or decrease the root font size, 1rem will always scale relative to that value.
Explain

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Vincent N.
Vincent N.
QA Consultant
Vincent Nguyen is a QA consultant with in-depth domain knowledge in QA, software testing, and DevOps. He has 10+ years of experience in crafting content that resonate with techies at all levels. His interests span from writing, technology, building cool stuff, to music.
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