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SEO Checklist 2021

Search engine optimization (SEO) is one of the core skills of the trade of Internet craftsmanship. This SEO checklist includes the most important aspects that will keep your website ranking on the first page in Google. This SEO checklist is updated for 2021.

SEO cheat sheet

To keep your website optimized for search engines you need to keep up your craft and remember to verify that all is in place. Here is a quick list of topics to remember:

SEO checklist livestream

Page title

The title of your page should be the most prominent and needs to use the HTML H1 tag. The placement of your main keywords should be as early as possible in the title tag. 


<h1>SEO checklist</h1>

Title and description meta tags

The title and description meta tags are being used by Google to display search results. Make sure you have title and description tags properly tagged up and that the title tag matches the H1 tag on your site and that the main keyword is also present in the description tag.


<title>SEO checklist</title>
<meta name=”title content=”SEO checklist”>
<meta name=”description” content=”SEO checklist ....”>

Canonical tag

The canonical tag is a housekeeping item. Each page should ideally only appear once with a unique URL on your website. The canonical URL defines the original source that search engines should use. In case of e.g. having multiple URLs or if your website is available with http and https or with and without www.

<link rel="canonical" href="">

Descriptive image alt and name

Google image search should not be underestimated. Make sure you use descriptive image names and alt text. Your images will rank higher and they can also be used for featured snippets in Google if you rank as #1.

Example code:

Google featured snippet screenshot

Use friendly URLs

Friendly URLs are simply URLs that use plain text and where the text reflects the main keywords of a given page. The following is an example of a friendly URL for a lounge chair product:

Validate HTML basics

Once you have your HTML basics in place you need to validate them. There are several tools you can use for this but Moz, Semrush and Ahrefs are the most popular.

Example of validation using Moz:

Moz SEO validation screenshot

Use internal links properly

Internal links are useful for your visitors to navigate but also for search engines. Make sure your anchor text is descriptive and represents the content of the page you link to. Read more about how to use hyperlinks properly

Example of an internal link to a blog post with the topic SEO checklist. Note the URL of the blogpost and the anchor text are matching. That is good.

<a href=””>SEO checklist</a>

Mobile friendly

Make sure your website is mobile friendly. This is an important point as you will get a penalty if your website is not mobile friendly. You can use the mobile friendly test from Google to verify that your site is actually mobile friendly.

Mobile friendly test screenshot

Site speed and core web vitals

Your site speed directly impacts SEO. Google introduced core web vitals in May of 2020 and are the new metrics used to measure the frontend performance of your website. We did some research on how much site speed affects your SEO ranking. You want to score your website in the green which means a Lighthouse score of 90+ for mobile.

You can use PageSpeed insights or measure to measure site speed. For global metrics numbers you can use Lighthouse metrics.

Global lighthouse metrics screenshot

Structured data

Add structured data to your website. Structured data is a way to add semantic information about the content on your webpage. Structured data schemas include: blog post, products, videos and recipes. Use Rich results test from Google to verify structured data.

Rich results test screenshot

Social sharing tags

Social sharing tags are used to show rich results in social media like Facebook, Twitter and LinkedIN. You can use to verify that your socal tags are correctly in place.

Meta tags validator screenshot


This is more of a housekeeping point, but do not forget to make your site secure with HTTPS. HTTPS is Faster than HTTP so it is good for user experience, but more importantly for SEO Google is giving a penalty if you are not using HTTPS.

Use 301 or 308 redirects

When you change a URL and want to keep the SEO juice you need to define redirects. Use 301 or 308 redirects for legacy URLs so search engines know that they are permanently moved. 308 is the latest recommendation for permanent redirects.

Running a store?

The best SEO practices are changing rapidly, and keeping up has become incredibly hard. On the other hand, if your product is not appearing in search engine results, you are losing $ big time. To help you stay in the loop of SEO and successfully drive organic traffic in 2022 check out the link and download the free .pdf version of it.

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