On the affected page, open the Firefox menu and click the percentage between the zoom buttons. You can also press Ctrl+0 on Windows or Linux, or Command+0 on Mac. This resets the site to your Firefox default, which may be higher or lower than 100%.
01Compare two different sites
Section linkIf one site looks wrong, reset it and reopen a page on the same hostname. Firefox saves page zoom by hostname even after you close the browser. A news site and its help subdomain can therefore have different zoom levels. Test an unrelated site before changing the browser-wide default.
02Check the default if several sites look wrong
Section linkIn Firefox Settings, look for Default zoom under Accessibility. If your version has no Accessibility panel, look under General → Language and Appearance → Zoom. Choose the baseline you want. Firefox remembers zoom levels you previously set on individual sites, so reset an affected site if it still looks different from your new default.
03If only the letters change size
Section linkCheck Zoom Text Only in the zoom settings. Turn it off if you want zoom to resize the entire page, including images. If text still looks too large or crowded, also check Minimum font size in the advanced font settings. If the toolbar and other apps are enlarged as well, check your system display settings separately.