Why the audit is important
Reducing the total size of network requests speeds up page load time and saves your users money that they would have spent on cellular data.
See Highest Correlation To Load Time to view the correlation between requests and load time.
See What Does My Site Cost to calculate the cost of viewing your site around the world. You can adjust the results to factor in purchasing power.
How to pass the audit
Click View Details to see your page's requests. The largest requests are presented first. Reduce the size of the requests to reduce your total payload size.
Here are some strategies for reducing payload size:
- Defer requests until they're needed. See The PRPL Pattern for one possible approach.
- Optimize requests to be as small as possible. Possible techniques include:
- Cache requests so that the page doesn't re-download the resources on repeat visits. See HTTP Caching and Service Workers: An Introduction.
How the audit is implemented
This section explains how this audit is implemented, so that you can understand how the audit's score is calculated.
Lighthouse sums up the total byte size of all resources that the page requested.
The target score of 1600KB is based on what a page can theoretically download on a 3G connection, while still achieving a time-to-interactive of 10 seconds or less. See googlechrome/lighthouse/pull/1759 for the original discussion.
The 0 to 100 score is calculated from a lognormal distribution.