Lighthouse Score

The Lighthouse score is the 0 to 100 number shown by Google's open-source Lighthouse auditing tool. The performance score is a weighted blend of several lab metrics, each converted to a score by comparing it with real-world data distributions. Ranges are 0-49 (poor), 50-89 (needs improvement) and 90-100 (good).

Why it matters

It gives teams a simple, repeatable target and a list of specific fixes. Current versions weight metrics roughly as follows: Total Blocking Time and LCP carry the most, CLS, FCP and Speed Index the rest. Weights have changed between versions, so a score can shift after a Lighthouse upgrade without any change to your site.

Example

FCP 1.4s    -> 0.89
LCP 3.1s    -> 0.62
TBT 450ms   -> 0.55
CLS 0.02    -> 1.00
Speed Index 3.0s -> 0.80
Weighted performance score: about 70

These numbers are illustrative only.

Common mistakes

• Treating it as a ranking factor. Google ranks on Core Web Vitals field data, not the Lighthouse number.
• Comparing scores across tools or devices; throttling settings differ.
• Running it once. Results vary by several points between runs.
• Chasing 100 at the cost of features users value.

Related

• Core Web Vitals
• TBT
• PageSpeed Insights
• Field data vs lab data

यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.