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.
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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:
- Format page header with H1
- Add title and meta description tags
- Add canonical tag
- Use descriptive image names and alt text
- Use friendly URLs
- Validate HTML basics using Moz, Semrush or Ahrefs
- Use proper internal hyperlinks
- Verify your site is mobile friendly
- Measure core web vitals and keep score 90+
- Add structured data
- Validate structured data
- Use HTTPS
- Use 301 or 308 redirects for legacy URLs
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.
Example:
<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.
Example:
<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="https://example.com/blog/seo-checklist">
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:
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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:
www.example.com/products/lounge-chair
Validate HTML basics
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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=”https://example.com/blog/seo-checklist”>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.
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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 web.dev measure to measure site speed. For global metrics numbers you can use Lighthouse metrics.
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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.
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Social sharing tags
Social sharing tags are used to show rich results in social media like Facebook, Twitter and LinkedIN. You can use metatags.io to verify that your socal tags are correctly in place.
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HTTPS
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.