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Chris Bongers
Chris Bongers

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Optimizing the PageSpeed results - part 17

You probably thought that was right. The portfolio is done and dusted.
But now that it's live, we have to ensure people visiting our website have the best possible experience.

So in today's article, we will conduct a PageSpeed exam and address any issues we find.

The initial pagespeed

You can use this fantastic website powered by Google to perform a basic report for your website.

Visit the PageSpeed Insights website

Fill out the URL to your website and click the "Analyze" button.

For my portfolio, I got the following results on mobile.

Screenshot 2022-10-14 at 08.04.30.png

I'll be honest with you. We did well out of the box.
We score 100 on Desktop and 89 on mobile.

Both have the same remarks. Our images can be optimized!

So let's tackle that issue and see what effect it has.

Optimizing images with Next/Image

You might have noticed I used the project's default HTML <img /> tags.

There is an alternative we can (and should) use in Next.js, which is their wrapper called <Image />.
This component ensures all required props are set and will do some magic caching and sizing for us.

Let's open the project and open up the introHeader.js file and start by importing the next/image package like this:

import Image from 'next/image';
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Then modify the image to use the new tag.

  alt='Image of Chris'
  className='z-10 relative rounded-full'
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Yep, as easy as that, and our image will now be as optimal as possible.

The other image we use is actually on the work component.

So again, open up the work.js component and load the next image lib.

import Image from 'next/image';
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This one is slightly different from before we had the image in the root.
The image is also responsive, making it a bit more complicated with Next/image. So I added a wrapping div with the styling like this.

<div className='w-full md:w-1/3 mb-3 md:mr-6'>
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You can also see we set the layout to be responsive, which ensures that the image scales nicely on mobile.

However, if we now run our application, we quickly see a Next.js error that the domain is not a valid source for images.

This is because it's a strict setup, and we must set our website to allow this domain explicitly.
Open up the next.config.js file and add the images prop like this.

const nextConfig = {
  images: {
    domains: [''],
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And now our images will load perfectly!

Putting it to the test

Let's deploy our changes and re-run the PageSpeed test.

Final PageSpeed result

Wow! We also got a 100 score on mobile now, and all the recommendations are gone.

Well done to us. Our users will also be happy to get a faster and more optimized website.

If you want to check out the changes, view this GitHub branch.

Thank you for reading, and let's connect!

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Top comments (1)

aradwan20 profile image
Ahmed Radwan

Good one Chris