Simon Willison’s Weblog

viewport-preview (via) I built a tiny tool which lets you preview a URL in a bunch of different common browser viewport widths, using iframes.

Posted 26th July 2022 at 12 am

Recent articles

Fly's new Sprites.dev addresses both developer sandboxes and API sandboxes at the same time - 9th January 2026
LLM predictions for 2026, shared with Oxide and Friends - 8th January 2026
Introducing gisthost.github.io - 1st January 2026

css 231 iframes 21 mobile 40 projects 515 testing 66

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