Unit Rulebook

Type a unit, or a word from its description.

    About

    CSS Unit Rulebook is a reference for every CSS unit, written by Konstantin Beregovoy.

    Author

    Konstantin is a frontend engineer who works on accessibility. More about the work is on bereg.dev.

    Licenses

    Code
    MIT LicenseUse it for anything, keep the copyright notice.
    Text
    CC BY-NC-ND 4.0Read it, quote it and share it with credit: "CSS Unit Rulebook" by Konstantin Beregovoy, with a link to units.bereg.dev. Not for sale and not for altered copies; the book stays with the author.
    Data
    CC BY 4.0Formulas, the list of units, the CSS examples and the computed browser support, as in /units.json. Use them with the same credit.
    Fonts
    SIL Open Font License 1.1IBM Plex Sans and IBM Plex Mono, served from this site. The license text is linked.

    Browser support data

    The support tables are generated from MDN browser-compat-data 8.1.7, checked on 2026-11-01. That data is published under CC0 1.0, so it carries no credit requirement. It is a copy taken on that date, and browsers move on.

    browser-compat-data on GitHub