Preloading, Prefetching and Preconnecting
These three techniques are hints we give the browser about what it will need next, so it can get a head start instead of waiting until the last moment. Used carefully, they shave noticeable time off how fast a page becomes useful.
Each does a slightly different job, and using the right one in the right place is what makes them effective.
Small Hints, Real Gains
These hints are modest in effort but can be surprisingly effective. By telling the browser what it will need a moment before it asks, we remove small delays that, added together, make the difference between a page that feels quick and one that feels hesitant.
What They Are Not
These hints are easy to misunderstand. They do not make a slow site fast on their own; they simply help the browser order its work better. Used as a substitute for real optimisation, they disappoint.
- They are a refinement, not a cure for a heavy page.
- Overusing them removes any benefit.
- They work best alongside other improvements.
- We apply them only where they clearly help.
How We Apply Them Safely
These hints are most effective when used sparingly on the few resources that truly matter. Mark everything as urgent and the browser has no way to prioritise, which can leave you no better off.
- Preload only the single most important asset, such as the hero image.
- Preconnect to the handful of external services you rely on early.
- Prefetch the next page only when the journey is predictable.
- Measure before and after to confirm the hints helped.
The Three Hints
Think of them as planning ahead: fetching what is definitely needed, warming up connections, and guessing what comes next.
| Hint | What it does | Good for |
|---|---|---|
| Preload | Fetches a key resource early | Hero image, main font |
| Preconnect | Opens a connection in advance | Fonts, APIs, CDNs |
| Prefetch | Fetches likely-next resources | The page users click next |
Frequently Asked Questions
Can these hints make a site slower?
If overused, yes — telling the browser everything is urgent helps nothing. We apply them selectively to the few resources that genuinely matter.
If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.