A Practical Guide to Core Web Vitals
Performance improvement starts with real experience data, then addresses the largest element, interaction delay, and layout stability.
Performance improvement starts with real experience data, then addresses the largest element, interaction delay, and layout stability.
The decision that should precede delivery
Compress and size images, reduce unnecessary JavaScript, and prioritize critical fonts and resources. Monitor after every release because lab averages do not represent every user.
Test the sequence with real copy in both directions before polishing decoration. Record where users hesitate, what information is missing, and whether the task works by keyboard and on mobile.
A reviewable checklist
- Optimize the hero image
- Avoid needless render blocking
- Reserve media dimensions
- Set a CI performance budget
Review questions before scaling
- Has the team documented: Optimize the hero image?
- Has the team documented: Avoid needless render blocking?
- Has the team documented: Reserve media dimensions?
Keep each answer beside the decision, owner, and review date. If the required signal is unavailable, reduce the experiment instead of expanding delivery scope.
Turn the insight into an action
Choose one decision you can apply this week, assign an owner and success signal, then review the result before expanding scope.