We test every page on a $150 phone
Why our speed numbers come from a mid-range Android phone on a slow connection, and what that changes in how we build.
Developer laptops are fast and sit on office broadband. Most visitors to the sites we build are on a phone that cost a few hundred dollars, often on a mobile connection.
So every template we ship is measured on a mid-range Android phone over a throttled connection. We record the time until the largest piece of content appears, any layout shift, and how long the page ignores taps.
What it changes
- Images. The first image on a page loads at once; every other image waits until it is painted.
- Fonts. One font file at most, cut down to the characters the site uses.
- Scripts. A script has to earn its place. Menus and accordions work without one.
The target
Largest content under 2.5 seconds on that phone, no layout shift, and no delay to taps. Our median for launched sites this year is 1.3 seconds.