PX to EMPX to REMFree

1.0000em

16px / 16px parent

1.0000rem

16px / 16px root

CSS Output

font-size: 1.0000em; /* 16px */font-size: 1.0000rem; /* 16px */

Quick Reference

10px
0.625em
12px
0.750em
14px
0.875em
16px
1.000em
18px
1.125em
20px
1.250em
24px
1.500em
32px
2.000em

How It Works

1

Enter Sizes

Input target and parent font sizes in pixels.

2

Calculate

Configure options and preferences.

3

Get Results

Copy output or view results instantly.

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About EM Calc

When you need developer and design work done in seconds, EM Calc delivers a clean, focused interface without the friction of a generic tool. Everything happens client-side, which means your files and data never leave your machine. The interface is intentionally minimal so you can focus on the task instead of learning the tool. If you find yourself doing this regularly, the rest of the developer suite covers most adjacent tasks with the same approach.

When you'd reach for EM Calc

  • You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.

    Marketers and ops people whose primary tool is metered.

    Stay productive without burning credits.

  • You're on a public or shared machine and don't want to leave traces of what you're working on.

    Travelers, contractors, anyone working from a friend's computer.

    Nothing is uploaded, nothing persists if you're not signed in.

  • You're cleaning up a folder of files that accumulated over a project and need to standardize them.

    Designers, writers, and developers wrapping up deliverables.

    Drop each file in, copy the output, move on.

  • You need to handle a one-off task right before a meeting and don't have time to install anything.

    Anyone working remotely on a borrowed or restricted machine.

    Open the page, get the result, paste it into your doc — under a minute.

Frequently asked about EM Calc

Is EM Calc really free?
Yes — EM Calc is free for unlimited personal use, with no account required and no watermark on the output.
Does EM Calc work on mobile?
Yes, EM Calc is fully responsive and tested on iOS Safari and Android Chrome.
Do I need to create an account to use EM Calc?
No. EM Calc works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
Are my files uploaded to a server when I use EM Calc?
EM Calc processes everything in your browser using local APIs. Your files never leave your device.
Will EM Calc change my original file?
Never. EM Calc only reads your input file and produces a new output file.

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