Pixel Converter

The free pixel converter for CSS units and paper sizes.

Convert pixels into CSS units such as em, rem, pt, and vh — plus absolute measurements like inch, centimeter, and millimeter, and standard A, B, C, and US paper sizes. Pick a conversion below.

px to empx to rem

EM

px to emem to px

REM

px to remrem to px

PT

px to ptpt to px

Viewport Height (VH)

px to vhvh to px

INCH

pixels to inchesinches to pixels

CM

pixels to centimeterscentimeters to pixels

MM

pixels to millimetersmillimeters to pixels

A and B Paper Sizes

A Paper Sizes to pixelsB Paper Sizes to pixels

C and US Paper Sizes

C Paper Sizes to pixelsUS Paper Sizes to pixels

One toolkit for every pixel conversion

Front-end and email developers constantly translate between units. A design comes in pixels, a design system wants rem, a print spec asks for points, and a physical layout needs centimeters. This pixel converter puts every one of those conversions in a single place, each with the exact formula, a live result, and a reference table you can scan at a glance.

The CSS unit converters — px to em, px to rem, px to pt, and px to vh (and their reverses) — let you set the base font-size or viewport so the relative math matches your actual document. The physical converters — pixels to inches, centimeters, and millimeters — use the 96 DPI CSS reference by default and let you switch to a print resolution like 300 DPI. And the paper-size converters turn ISO A, B, and C sizes plus US Letter, Legal, Tabloid, and ANSI formats into exact pixel dimensions for any DPI.

Everything runs locally in your browser — no signup, no uploads, no waiting. Bookmark the conversion you use most, or start from the list above.

Pixel Converter FAQs

The Pixel Converter is a free, browser-based toolkit for converting pixels into CSS units like em, rem, pt, and vh, as well as physical measurements like inches, centimeters, and millimeters. It also converts standard A, B, C, and US paper sizes into pixel dimensions. Every conversion runs instantly on your device — nothing is uploaded.
Absolute pixels do not scale with a user’s font-size preference. Converting to relative units like em and rem makes typography and spacing accessible and responsive, while pt is the standard unit for print and word processors. Each converter shows the exact formula and a reference table so you can move between units confidently.
Screen pixels map to physical lengths through a resolution (DPI). CSS defines a reference of 96 pixels per inch, which is the default here, and you can change the DPI for print work (typically 150 or 300). At 96 DPI, 1 inch = 96px, 1cm ≈ 37.8px, and 1mm ≈ 3.78px.
The toolkit covers the full ISO A series (A0–A10), B series (B0–B10), and C series (C0–C10, used for envelopes), plus US sizes including Letter, Legal, Tabloid, Ledger, and the ANSI A–E engineering series. Pick a size and DPI to get exact pixel width and height.
Yes — completely free, no signup, and fully private. All conversion math happens client-side in your browser, so no values are ever sent to a server.