BidirectionalReference Table100% Private

Reference Table (base: 16px)

How It Works

1

Set Base

Choose your root font size (default 16px).

2

Enter Value

Type a px or rem value to convert.

3

Copy Result

Use the converted value in your CSS.

Frequently Asked Questions

What is the default base font size?
Browsers default to 16px. You can change the base in this tool to match your project settings.
Why use rem instead of px?
Rem units scale with the root font size, making designs more accessible and responsive to user preferences.
How is rem calculated?
rem = px / base. For example, 24px / 16px base = 1.5rem.
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About PX to REM

PX to REM was built for the moment you just need to handle developer and design work and move on — no signup, no upload to a third-party server. The goal was to keep the path from "open the page" to "get the result" as short as possible. No mandatory account, no cookie wall, no upsell at every step. It is one of about a hundred developer tools that share the same philosophy: do one thing, do it well, get out of your way.

When you'd reach for PX to REM

  • 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'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 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 PX to REM

Is PX to REM really free?
Yes — PX to REM is free for unlimited personal use, with no account required and no watermark on the output.
Will PX to REM change my original file?
Never. PX to REM only reads your input file and produces a new output file.
What browsers does PX to REM support?
Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
Do I need to create an account to use PX to REM?
No. PX to REM works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
Does PX to REM work on mobile?
Yes, PX to REM is fully responsive and tested on iOS Safari and Android Chrome.

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