Matt Leaverton

Software and Electronics.

Currently Senior Software Engineer at Glowforge

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Font Size Bookmarklet

Messing around with bookmarklets and found this handy bookmarklet editor with some example bookmarklets here at I've been using the Increase Font Size one regularly when a site's text is too small to read comfortably - this increases the size of all fonts on the page by 25% every time you click on it.

From the site linked above - here is the base javascript:

let elms = [...document.querySelectorAll('*')];

for (let elm of elms) {
    let cs = getComputedStyle(elm);
    let fs = cs['font-size'];
    elm.oriSize = parseFloat(fs);

for (let elm of elms) {
    let fs = 1.25 * elm.oriSize; = fs + "px";

And here is the bookmarklet version - make a new browser bookmark and set the following as the URL: