A practical checklist for lazy loading

The advice here is unglamorous, which is probably why it gets skipped. Run through this the next time lazy loading comes up.

Speed is a feature people notice only in its absence, and then they leave rather than complain. Most teams find the first pass takes an afternoon and the maintenance takes minutes a month.

The checklist

• Only load what is about to be seen
• Never lazy-load the main hero image
• Always reserve the space so nothing jumps
• Someone is named as the owner
• There is a date to review it again

The reason this keeps coming up

Only load what is about to be seen. None of that requires a large budget, only a decision and someone to own it. The teams that stay on top of it are the ones who put it on a calendar rather than a wish list.

How to tell if yours is fine

Real-world numbers from actual visitors matter more than a score produced on a fast laptop. Three things worth confirming about lazy loading before you move on:

• Someone can say what the current setup is without going to look
• Never lazy-load the main hero image — and you know whether that is true here
• There is a way to tell whether the last change to this helped

If you want a second opinion on how yours is set up, ask.