Lighthouse Score
Design Processes
An automated audit that grades a page on performance, accessibility, best practice and SEO.
In practice
Lighthouse is Google's open-source tool that loads a page in a controlled lab environment and produces scores out of 100 for performance, accessibility, best practices and SEO, plus a list of specific fixes. It is a diagnostic, not a verdict — lab conditions differ from real devices — but it is the fastest way to find what is holding a page back.
Questions
What is Lighthouse Score?
A Lighthouse score is the result of an automated lab audit that measures a page against performance, accessibility, best-practice and SEO checks and reports each as a score with actionable findings.
Why do you use Lighthouse Score?
It turns 'make the site better' into a ranked list of concrete things to fix, and it catches accessibility failures nobody noticed.
How do you use/apply Lighthouse Score?
Run it in Chrome DevTools or PageSpeed Insights, read the failed audits rather than the headline number, fix the highest-impact ones, and re-run.
When do you use Lighthouse Score?
Before launch, after any significant change, and periodically — scores drift as content and scripts accumulate.
Who uses Lighthouse Score?
Developers, designers and anyone responsible for a site's quality.
