Store speed checklist: 20 items you can check today
Twenty checks a store owner can run on a phone in an hour, each with what to look for and what to do about it.
How to run it
Use a phone, or the browser’s mobile view with the network set to a slow mobile profile, and open the best-selling product page, the busiest collection and the homepage. Keep the network panel open for the first group. Mark each item pass, fail or not applicable, and note the fix next to each fail.
What loads
| Check | What to look for | Fix if it fails |
|---|---|---|
| 1. Hero video | Does a video file load on the homepage before you press play? | Poster image; load on play; move brand video to an about page |
| 2. Largest image | Is the main product image several times larger in pixels than the space it fills? | Correct sizes from the platform’s image service; theme requesting the right size |
| 3. Images below the fold | Do gallery and collection images load before you scroll to them? | Lazy-loading below the first screen |
| 4. Image dimensions | Does the layout jump as images arrive? | Width and height set; space reserved |
| 5. Third-party domains | How many domains other than yours load scripts on the product page? | Audit each: remove, defer or load on interaction |
| 6. App scripts | Which apps inject scripts on this page, and does the page use them? | Remove unused apps; choose apps that render server-side |
| 7. Pixels and tags | Do advertising pixels load before consent and before the page is interactive? | Load after consent and after interactive, in one tag setup |
| 8. Fonts | Are fonts loaded from a third-party service, and does text appear late? | Self-host; preload; limit weights |
What the page does
| Check | What to look for | Fix if it fails |
|---|---|---|
| 9. Variant tap | Does tapping a variant respond immediately or hesitate? | Reduce scripts on the page; lighter variant handling |
| 10. Add to cart | Does add-to-cart respond within a blink? | Same: main-thread work from apps and theme |
| 11. Slider | Is there a slider or carousel on the homepage or product page? | Replace with a static hero or a simple list |
| 12. Pop-ups | Does a pop-up appear on first visit and shift the page? | Native section, deferred, shown once, no layout shift |
| 13. Chat widget | Does a chat script load for every visitor on every page? | Load on interaction or on specific pages |
| 14. Reviews | Does the review widget fetch from a third party on load? | Reviews rendered into the page; interactive parts on demand |
How it is measured
| Check | What to look for | Fix if it fails |
|---|---|---|
| 15. Field data | Do the real-user reports show the product and collection templates passing on mobile? | Work the failing template using the checks above |
| 16. Trend | Have the mobile numbers worsened since last quarter? | Compare with the app and theme change log; undo the cause |
| 17. Lab diagnosis | Does a lab run on a mobile profile show a waterfall you can read? | Use it to find the specific image, script or app |
What keeps it fast
| Check | What to look for | Fix if it fails |
|---|---|---|
| 18. Theme currency | Is the theme updated, through a duplicate and preview? | Update; test; publish in a quiet window |
| 19. App audit date | When was the app list last reviewed with a measurement? | Quarterly audit with before-and-after lab checks |
| 20. The rule | Is anything added to the page without a measurement and an owner? | Adopt the rule; record additions with owner and measurement |
Frequently asked questions
Do we need a developer to run this checklist?
No. The checks use a phone, a browser and the store's own reports. Some fixes need a developer, such as theme changes, but most are removing an app, changing a setting, replacing an image or turning off a feature. Run the list, mark what fails, and hand the developer only the items that need code.
Which items matter most?
The first group, what loads on the product page: video, images, app scripts, pixels. Those decide most of the weight and most of the delay. If time is short, run the first eight items on the best-selling product page and act on those.