px to rem: CSS Unit Converter

Font size, type scale, pt, dp

Only for iPhone

Free · In-App Purchases · Designed for iPhone. Not verified for macOS.

iPhone

Set your own root size and see px, rem, em, pt and % at once — plus modular type scales, 4/8pt spacing tokens and copy-ready CSS variables. px to rem, rem to px, em, pt and % — converted the moment you type, against the root font size your project actually uses. Most converters assume a 16px root and stop there. This one lets you set the root font size, the em context size and the DPI once, then recomputes everything against that base: live conversions, type scale, spacing tokens and the cross-platform density table. It is a native iPhone tool, so there is no browser tab to hunt for and no connection required. WHAT YOU GET - Every unit at once: enter one value and read px, rem, em, pt and % side by side, each copyable with a single tap - Your own base: root size (8-32px), em context (8-48px) and DPI (72-320) sliders, so a 62.5% root or a non-96 DPI setup gives correct numbers instead of textbook ones, remembered between launches - One tap to reset the base back to web defaults (16px root / 96 DPI) - Modular type scales: pick a base size and a ratio — Minor Second 1.067, Major Second 1.125, Minor Third 1.200, Major Third 1.250, Perfect Fourth 1.333, Augmented Fourth 1.414, Perfect Fifth 1.500 or Golden Ratio 1.618 — and get Display, H1, H2, H3, H4, H5, Base, Small and Caption in px and rem with an "Ag" size preview - Copy-ready CSS: export the whole type scale or spacing set as :root custom properties, written in rem with px comments - 4pt and 8pt spacing token tables in px and rem, each token with a visual bar - Common breakpoint reference: 640, 768, 1024, 1280 and 1536 px, shown in px and rem together - Pin a conversion with a star or save it to history: the Saved tab has Pinned and Recent sections, per-entry unpin and delete, and a mini all-units breakdown - On-screen numeric keypad with a decimal point and backspace, plus haptic feedback on taps PERFECT FOR - Front-end developers turning a design file into real stylesheet values - UI and product designers keeping type and spacing consistent across screens - Design system maintainers who want one source of truth for their tokens - Anyone learning why rem, em and % behave differently: the Learn tab has six expandable articles with code samples (px vs rem vs em vs pt, rem and accessibility, percent and font-size, DPI/PPI, modular type scales, 4pt and 8pt grids), a cheat sheet (16px = 1rem = 12pt = 100%) and references to MDN, W3C, WCAG 2.2, and Apple HIG WHY NOT JUST USE A WEB CONVERTER? A web converter forgets your base the second you close the tab, handles one value at a time, and gives you nothing to paste. Here your root size, context size and DPI persist, results appear in all five units simultaneously, pinned values stay in a Saved tab, and the type and spacing scales come out as CSS you can drop straight into a stylesheet. The math runs on the device, so it keeps working anywhere the signal drops out. PRIVACY Everything is computed and stored on your device. No account, no sign-in, no ads, no analytics SDK, no data leaves your phone. The app works completely offline. There is one optional local daily reminder at 19:00 that you can turn on or off. FULL ACCESS Full access unlocks the modular type-scale generator, the CSS variable export, the 4pt/8pt spacing and cross-platform density tools, plus unlimited pinned conversions and saved history. Choose a weekly plan, a yearly plan, or a one-time lifetime purchase. Payment is charged to your Apple Account at confirmation. Subscriptions renew automatically unless cancelled at least 24 hours before the current period ends, and can be managed or cancelled in your App Store account settings. The lifetime option is a single purchase and does not renew. Restore purchases is available. Set your root size, type your first value, and paste the result straight into your stylesheet. Terms of Use (EULA): https://web-levi.web.app/terms Privacy Policy: https://web-levi.web.app/privacy-policy Questions? tphuc.work@gmail.com

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Bug fixes and performance improvements.

Version 1.1.1

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The developer, Phuc Pham, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

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    Information

    Seller
    • Phuc Pham
    Size
    • 4.4 MB
    Category
    • Graphics & Design
    Compatibility
    Requires iOS 17.0 or later.
    • iPhone
      Requires iOS 17.0 or later.
    • Mac
      Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    • English
    Age Rating
    4+
    In-App Purchases
    Yes
    • Spacing & Breakpoints Lifetime $29.99
    • Root Font Size Weekly $2.99
    • Design System Yearly $14.99
    • Learn More
    Copyright
    • © 2026 Phuc Pham
  • Developer Website
  • Privacy Policy

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