When response compression is worth the effort

It comes up on almost every project, usually later than it should. Response compression is not free, and pretending otherwise leads to bad decisions.

Real-world numbers from actual visitors matter more than a score produced on a fast laptop. Check it against what you would want a competitor's site to get wrong.

When it is worth it

Text compresses dramatically and costs almost nothing to enable. In practice this is a scheduling problem more than a technical one. If two people in the business would answer this differently, that gap is the actual problem.

When it is not

If nothing downstream depends on it and nobody is complaining, it can wait. Where this goes wrong is almost never a lack of knowledge.

How to decide

Already-compressed formats gain nothing from it. The cost of getting this wrong is rarely visible on the day it happens. Anything you cannot measure here, you are deciding by taste, which is fine as long as everyone knows it.

The short version

Speed is a feature people notice only in its absence, and then they leave rather than complain. Three things worth confirming about response compression before you move on:

• Someone can say what the current setup is without going to look
• Already-compressed formats gain nothing from it — 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.