Tue 09 June 2026

Lottie Website Tester

Posted by Al Sweigart in misc   

A free, single-file website tester that finds broken links, slow pages, and bloated pages on your site — no signup, no paywall, no subscription nagging, no install. Download lottie.html, upload it anywhere on your domain, and open it in your browser. That's the whole install. I generated a small web page for this tool if you're into that sort of thing.

Every time I wanted to check my own websites for broken links and page-weight problems, I ran into the same wall: the tools that did this well either wanted me to create an account, locked the useful features behind a paid tier, or required a complicated install with Node, Docker, Python virtualenvs, browser extensions, or a desktop client.

I just wanted to point a thing at my site and have it tell me what's broken. So I made one. It's a single .html file. There's no backend, no telemetry, no account, no payment screen, no install wizard — just open the file in a browser and use it.

It will never have a "Pro" tier. There is nothing to sign up for. You own the file.

More instructions on the git repo.


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