Editing

Check how your site looks on mobile and tablet

Most visitors arrive on a phone. The device switcher shows you exactly what they'll get, before you publish.

1
Find the device switcher above the site
Desktop, Tablet and Mobile sit in a small bar directly above the canvas, in both Preview and the editor.
2
Pick a size
Tablet renders at 834px — an iPad held upright. Mobile renders at 390px — a current iPhone in portrait. The frame narrows and the site re-lays itself out.
3
Fix anything that looks wrong, right there
The switcher works in the editor too, so you can shrink an oversized heading or swap an image while looking at the phone layout rather than guessing from desktop.

Worth knowing

This is the real layout, not an illustration of one. The site's own responsive rules run against the narrowed frame exactly as they would on the device, so what you see is what a phone renders.
Every Webese site is also protected against the commonest causes of a page sliding off the edge of a phone screen — oversized images, rows that refuse to stack, long unbreakable links — applied automatically each time you publish.
The switcher is hidden when you're building on a phone yourself, where the canvas is already phone-width.

My site was built before this existed. Is it protected too?+

Yes. The mobile protections are applied at publish time, so an older site picks them up the next time you hit Publish — no rebuild needed.