Does Postscript slow down a store?
In 7IT’s test of 367 US online stores, Postscript ran on 24 of them (6.5%). At first load it is light: a median of 4 KB and 0.00 s of phone time. Google’s test measures the first load only, so anything it loads after a visitor interacts is not in these numbers.
Stores with it and without it.
| Stores | Median score | Main content | Blocking time | Apps on the page | |
|---|---|---|---|---|---|
| With Postscript | 24 | 31 | 10.3 s | 2063 ms | 27 |
| Without | 343 | 34 | 11.8 s | 1267 ms | 19 |
Stores that run Postscript had a median score of 31, against 34 for stores without it. They also run more apps overall (a median of 27 against 19), so that gap is not all Postscript’s doing. The size and phone time above are Postscript’s own. On this sample there is no score penalty that can be pinned on it.
One in four stores that load it download more than 4 KB of it, and spend more than 0.00 s running it. Median Google phone-lab results, home pages only, September 2026. Method and limits in the study.
If you run Postscript.
- Pop-up and sign-up scripts rarely need to run before the page appears. Load them after the first scroll or after a few seconds on the page.
- Do not show a pop-up on the first page a visitor from an ad lands on. It costs speed and the first impression at once.
- Keep the signup form on the page (footer, checkout) and let the script that draws the pop-up wait.