Arimo

Arimo is Steve Matteson's metric-compatible open sans-serif, released on Google Fonts in 2010 as the webfont incarnation of Liberation Sans. Every character occupies exactly the width its Arial counterpart does, and the line metrics match as well, so text set in one reflows identically in the other. The drawing follows the same neo-grotesque model — closed apertures, level terminals, and the deliberately unexpressive rhythm that makes Arial invisible on a page.

That turns the substitution for Arial into a mechanical operation rather than an approximation. Documents and layouts built around Arial keep their line breaks, page breaks, and pagination when Arimo takes over, which is the whole value: fidelity, not reinterpretation. Reach for it when a file or design has to survive being rendered on a machine that doesn't have Arial licensed — templates, PDFs, web builds, and office documents crossing between platforms.