In short
A set of limits on the technical metrics of a web page, agreed before build and enforced through automated checks after each deployment.
A performance budget might cap page weight at 500 KB, Time to First Byte at 200 ms, and LCP at 2.5 seconds.
Where it bites
Performance budget matters when slow pages, blocked interactions, or regressions start costing conversions. It keeps performance measurable before customers feel the delay.
What to check
- Which metric is the user actually feeling?
- What threshold fails the budget?
- Which deployment check catches regression first?
Common questions
What is Performance budget?
A set of limits on the technical metrics of a web page, agreed before build and enforced through automated checks after each deployment.
Why does Performance budget matter?
Performance budget matters when slow pages, blocked interactions, or regressions start costing conversions. It keeps performance measurable before customers feel the delay.
What should you check first for Performance budget?
Which metric is the user actually feeling? What threshold fails the budget? Which deployment check catches regression first?