Metrically compatible fonts
In this page, I will show you fonts with characters that are the same width as some well-known typefaces. All of the fonts on this list are released under an open source license, allowing for unrestricted use, sharing, and modification. It is recommended that you check each font's license before downloading it.
Metrical compatibility means that if you start writing a text in Helvetica and then switch to Arial, the text's proportions will not change. Both Helvetica and Arial are available through proprietary fonts, which means that you have more restrictions and must pay a license to use them in a specific way. Free fonts allow you to have more control over them without having to pay a license fee.
Below are the names of some popular Windows fonts; clicking on them will show you their respective alternatives.
Arial / Helvetica
Arimo
Arial Narrow / Helvetica Condensed
You can use Liberation Sans Narrow, available at its own repository. I would recommend reviewing the license before using, as I heard it is confusing. LICENSE AGREEMENT AND LIMITED PRODUCT WARRANTY / GNU GENERAL PUBLIC LICENSE
Times New Roman / Times
Tinos
Courier New
Cousine
Georgia
Gelasio
Cambria
Caladea
Calibri
Carlito
Consolas
DMCA Sans Serif
Kind of a direct clone of the original font, with some glyphs different for no reason. Be aware that its creator is a shithead, but at least the font is public domain, so...
Sources:
http://xahlee.info/js/metrically_compatible_fonts.html
https://wiki.archlinux.org/title/Metric-compatible_fonts
https://en.wikipedia.org/wiki/Croscore_fonts
