Yesterday I wrote about cutting down big images and video to speed up your site, and that’s usually where the quickest wins are. But it’s not the whole story. There’s another thing that drags pages down, and it’s a bit sneakier because you can’t see it just by looking at the page.

I’m talking about third-party scripts. That’s a bit of jargon, so let me explain – it just means bits of code your website loads in from other companies. Things like chat widgets, tracking pixels, analytics, fonts, social media embeds, and spam protection. Each one is doing a job, but each one also has to be downloaded before your page is fully ready, and some of them are surprisingly heavy.

The tricky thing is they build up over time without anyone really keeping track. A plugin here, a marketing tag there, a tool someone trialled two years ago and never removed… and before you know it your page is loading a load of stuff that’s slowing it down for no good reason.

So this is basically a walk-through of how to open the network tab in your browser, what you’re actually looking for, and what to do if you find something you don’t think you need. You don’t need to be a developer for any of this – if you can right-click, you can do it.

What’s actually a “third-party script”, and why should you care?

Quick bit of background first. Your own website lives on your domain. A third-party script is anything the page pulls in from somewhere else – another company’s servers. Obviously some of these are essential (you probably do want your analytics, say). But each one is an extra thing to fetch, and you’ve got no real control over how fast that other company’s servers are.

And with Google clearly prioritising speed right now – for both SEO and GEO (getting your site picked up by AI tools) – a page that’s waiting around for half a dozen other companies to respond is exactly what you don’t want. So it’s worth a look.

How do you open the network tab?

This sounds far more technical than it is. The network tab is a built-in tool in every browser that shows you absolutely everything a page downloads – every image, every script, how big each one is, and where it’s coming from. Here’s how to open it in Chrome (it’s almost identical in the others):

  1. Open the page you want to check.
  2. Right-click anywhere on the page and choose Inspect. (Or press F12 on Windows, or Cmd + Option + I on a Mac.)
  3. A panel opens up – along the top of it, click the tab that says Network.
  4. Now reload the page (F5, or Cmd + R on a Mac). This is IMPORTANT – the network tab only captures things from the moment it’s open, so you need to reload to see the page load from scratch.
  5. Let it finish, then click the Size column header to sort everything biggest-first.

That’s it. You’re now looking at every single thing your page loads, ordered by how much it weighs. It looks a bit overwhelming the first time, but you don’t need to understand all of it – you’re just scanning for the big, obvious offenders.

What are you actually looking for?

A few things might jump out at you:

  • Anything big that isn’t an image or video. You’ve hopefully already dealt with those. So a large JavaScript file (a .js) near the top of the list is worth a closer look.
  • Domains that aren’t yours. There’s usually a column showing where each thing is loaded from. If you see company names you recognise – a chat tool, a marketing platform, a social network – those are your third-party scripts.
  • The same thing loading over and over. If one script is being requested multiple times on a single page, that’s a red flag worth flagging to your developer.
  • Stuff you simply don’t recognise. Old tracking pixels and tools nobody remembers signing up for are really common, especially on older sites.

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We found spam protection loading where it wasn’t needed – so what then?

We work with a big, busy site running on WordPress (well, we work with a few but this happened with one in particular), and when we ran their key pages through the network tab we noticed reCAPTCHA (that’s the “I’m not a robot” spam protection that sits on forms) was loading on loads of pages that didn’t actually have a form on them.

And that’s a genuine cost – reCAPTCHA pulls in its own scripts from Google every time it loads, so having it fire on a page with nothing to protect is just dead weight slowing things down for no reason. The fix is to only load it where it’s actually doing a job. On most WordPress setups that’s a setting in the plugin (or your developer can scope it to your contact and sign-up pages), so you keep the protection exactly where you need it and drop it everywhere you don’t.

It’s a small thing on one page, but across a big site with lots of traffic, those little savings really add up.

So what do you do if you spot something you don’t need?

It’s tempting to go in and rip out everything you don’t recognise, but please don’t do that!

The reason is that scripts often look pointless when they’re not. That mystery tag might be feeding a report someone on the marketing team relies on. That widget might be tied to a sign-up flow that breaks the moment it’s gone. So before anything comes off, do two things. First, check with the wider team – ask if anyone knows what it is and whether they’re using it. And second, get your developer to actually remove it, ideally one thing at a time so you can spot straight away if anything stops working.

So the order is always: spot it, check it’s not needed, then take it off. Not the other way round!

Where should you start?

Pick your homepage and one or two of your busiest pages – the ones that matter most for sales or sign-ups – and run them through the network tab using the steps above. Make a quick list of anything heavy or anything you don’t recognise, then take that list to your team and your developer rather than acting on it yourself.

It’s not the flashiest job in the world, but it’s one of those little wins that makes a real difference to how fast your site feels – and right now, fast really matters. If you’d like a hand going through your own site, please get in touch.