Free tool · no signup
404 page checker
We open a made-up address on your site and check that it returns a real 404, looks like your brand and gives visitors a way back.
Only public pages are read. Results are not stored.
Prompt: create a branded 404 page
Create a branded 404 page for my app: use my logo, colours and fonts, a clear heading such as "We can't find that page", one short friendly sentence, a button back to the home page and links to my main pages. Make sure unknown addresses show this page and return a real 404 status (not 200), and add <meta name="robots" content="noindex"> to it.
Frequently asked questions
- What is a soft 404?
- A missing page that returns status 200 instead of 404. Search engines may index these error pages, and monitoring tools can't tell broken links from real pages.
- Why does a branded 404 page matter?
- Mistyped or old links happen. A branded page with a way back keeps visitors on your site instead of leaving at a dead end.
- How do I fix it in Lovable?
- Copy the prompt on this page into Lovable, publish, then run this check again.
- Does SaaS Sentinel check this automatically?
- Yes. The daily brand checks for each app you monitor include the same 404 page check.
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