No matter how hard we try and how experienced we are, there are some common SEO mistakes that can be found even in the most well-optimized website. However, fret not: these mistakes are easy to discover and fix if you perform a comprehensive SEO audit.

If you didn't read our guide for a perfect SEO audit, now is the time to read it. These two articles are complementary to each other and we recommend using both when optimizing your website. We also recommend using Google Analytics to get stats on your target audience and relevant keywords, which are both ranking factors. Backlinks are also essential for your link building strategy. So, on to the list!

HTTP Status and Server Errors

HTTP status and server errors are the most common SEO mistakes that you might encounter in an audit. This type of SEO mistake is related to problems in the data transfer between the browser and the server; the dreaded error 404 falls under this category.

This type of error can affect your traffic severely since users tend to distrust websites with non-available pages and generally leave when faced with a 404 error page. ❌ Find the most common SEO mistakes of HTTP status and server errors below.

1. 4xx Codes

These codes indicate a broken page, which prevents users from being able to access it. A 4xx code can also mean that the page wasn't indexed.

2. Non-tracked pages

Non-tracked pages can result from two different issues: either the server timed out, or the server denied access to the page.

3. Internal broken links

These are links that take you to pages inside your website that no longer exist, affecting both SEO and user experience.

4. External broken links

These are links that take you to a page on another website that no longer exists, sending a negative SEO signal.

5. Broken image links

These happen when an image file is no longer available or the URL is incorrect.

6. Redirects

These can damage your optimization efforts too, and they can be either temporary or permanent.

Meta Tags

Meta tags make search engines understand what your pages are about. The text from the meta tags is also displayed on search engine result pages (SERPs), so it's extremely important to optimize these tags. Title tags and meta descriptions should include your target keywords, and at the same time be clear and concise.

We also recommend making sure there are no duplicates: title tags and meta descriptions should be unique for each page.

If these tags are not available, search engines will automatically pull whatever text they deem to be relevant from your page. Those excerpts most likely will not make any sense since they are collected and displayed automatically.

The title tags and meta descriptions you create for each page should also be the correct size 70 characters for the title tag and between 150 to 160 characters for the meta description. In some websites, it is hard to create unique title tags and meta descriptions for each page, which makes it necessary to invest even more in other aspects of SEO through SEO tools. However, the more you can use unique metadata for each page, the better it will be for your website. The following are the most common SEO mistakes when it comes to meta tags.

7. Duplicate title tags and meta descriptions

When you have several similar title tags and meta descriptions, it makes it difficult for any of them to rank for the keywords you're targeting, especially long tail keywords (which help rank for targeted searches).

8. Missing H1 tags

If you don't use H1 tags in your content, Google and other search engines will have issues analyzing your content correctly, even if it's high quality content.

9. Missing meta descriptions

When your meta descriptions are well-written and to the point, users are more likely to land on your website. Their absence might lead to low rankings and therefore, low search traffic.

10. Missing alt attributes

Alt attributes show Google and visually impaired users what your images are about. Using them correctly increases relevancy and traffic for your quality content, including blog posts that rank for more specific search terms.

11. Duplicate H1 and title tags

If there are several pages on your website using the same H1 tags and title tags, it's likely that cannibalization might occur. This is a phenomenon in which pages of the same website compete against each other on the Google rankings, disrupting any search engine optimization performed and resulting in a negative user experience.

12. Several H1 tags

Using more than one H1 tag on the same page will harm your optimization rather than improve it. Each page on your website should have one H1 tag only. This H1 tag should include your key phrase or search terms.

Duplicate Content

All elements of a page should be unique. So, marketers should make sure there is no duplicate content on your website, whether it is duplicating another website's content or another page on your own website. Whichever is the case, any instance of duplication is detrimental to your SEO strategy.

Duplication can also occur in URLs if you have a www and a non-www version of the same page.

When every element in page content and tags is unique, your website has a better chance of ranking higher. It is also going to be more relevant for your users. If you find two pages with the same content, the best you can do is use “rel=canonical” or a 301 redirect. ↪️

Missing Link Optimization

Links are of the utmost importance for user experience on your website. This includes both internal links (links toward other pages in your website) and external links (links that take you to other websites).

To make sure your website's architecture is up to date, you need to check if you have no broken links, whether internal or external. Some other links might have a nofollow attribute, or use HTTP instead of HTTPS – all these factors affect your rankings and your SEO strategy.

These are the most common SEO mistakes in link optimization.

13. HTTP pages in HTTPS websites

You probably already know your website should use HTTPS. However, when you add your SSL certificate, you need to make sure that you redirect all the pages to their HTTPS version. Otherwise, you'll end up with orphaned pages that still use HTTP.

14. URLs that contain underscores

We highly recommend using dashes instead of underscores in your URLs. Underscores might be misinterpreted by search engines, creating errors in your website's crawling.

Other common mistakes regarding link optimization are:

• Broken external links
• Broken internal links
• External links with nofollow attribute

Tracking Errors

Tracking errors can block your website from being correctly indexed by Google. That's why you should always make sure you detect any tracking errors on your website when auditing. If you correct any tracking errors, that's a great step toward better rankings.

You can avoid technical SEO issues by checking broken or blocked elements during your SEO audit. The absence of a sitemap.xml file or robots.txt file can also affect your rankings.

These are the most common issues when it comes to tracking.

15. Nofollow attributes in internal links

Internal links that contain the nofollow attribute keep your “link juice” from flowing from page to page.

16. Incorrect pages on sitemap.xml

Your sitemap.xml file should not include broken pages. Check if all your pages return a 200 code and that there are no redirects or missing canonical attributes.

17. Sitemap.xml not found

Including a sitemap.xml file on your website makes it a lot easier for search engines to explore, track, and index your website's pages.

18. Sitemap.xml absent in the robots.txt file

If your robots.txt file does not have a link to your sitemap.xml, SERPs won't be able to understand your website's architecture.

Other common tracking errors include:

• Pages not tracked
• Broken internal images
• Broken internal links
• Underscores in URLs
• 4xx errors
• Resources hidden on page links
• External resources blocked on the robots.txt file
• Nofollow attributes in external links
• Pages with one internal link only
• Orphaned pages in the sitemap
• Tracking depth over three clicks
• Temporary redirects

Indexing Errors

If a page is not indexed, it cannot be found by Google. When Google doesn”t find a page, it is unlikely that users will. Even when it doesn't seem like your website has tracking issues, there might be indexing errors Duplicate content can cause indexing errors because search engines don't know which page to rank for a specific keyword. This is a quite common SEO mistake, so make sure there are no duplicate title tags or H1 tags in your content.

When there is duplicate content , it is up to the search engine to pick which page to rank, which will be detrimental for some of those pages competing against each other.

These are the most commonly found issues with indexing.

19. Title tags that are too short/too long

If your title tag has under 60 characters, you might be losing an optimization opportunity; on the other hand, if it is too long, it's going to be shortened by SERPs.

20. Hreflang conflicts on the page's source code

If there is a hreflang conflict, websites in several languages might end up having indexing issues.

21. Hreflang link errors

If you use relative links instead of absolute ones, there might be hreflang issues. Make sure your absolute links are used when you're implementing hreflang.

22. Low word count

If your pages have less than 500 words each, we recommend increasing the word count. Longer content usually makes pages rank higher on search result pages.

23. Missing hreflang and lang attributes

When your website uses multiple languages, it is essential to use hreflang and lang attributes correctly. When these are missing, your SEO audit will show the above error, meaning there is no way to show each region the correct language.

24. HTML errors in AMP pages

When your HTML code does not follow AMP patterns, it will affect your website's performance on mobile devices.

These are other common indexing errors:

• Duplicate content
• Duplicate meta descriptions
• Hreflang language compatibility errors

Errors in the mobile version

In September 2020, mobile optimization will be one of the standard ranking criteria for all websites. Therefore, it is necessary to update your website according to AMP (accelerated mobile pages) standards, making sure it is mobile friendly.

AMP implies a few changes to your HTML, such as style, layout, or page templates. As of 2020, any mistakes in your HTML for AMP can affect your ranking.

Low website performance

When we talk about website performance, we mean first and foremost page speed. If you didn't read our page speed guide , we recommend checking it out. Page speed affects not only your users, in the sense that users will leave your page if it takes too long to load, but also affects the way Google perceives your page, making you rank higher or lower. ↗️

The following are the most common issues with website performance.

25. HTTP and HTTPS pages mixed up

It is common, as we mentioned previously, to have HTTP and HTTPS pages mixed up. You need to find a common standard for all of your pages, preferably in HTTPS. If you set up an SSL certificate, you need to change all your pages to HTTPS.

26. Javascript and CSS not cached

If the browser cache is not active, your website might take longer to load.

27. Javascript and CSS files not compressed

Compressing these files will help your page load faster. The easiest way to do this is by removing lines, comments, and blank spaces from your code.

How to check for SEO mistakes using SERPed

If you use SERPed.net, it's easy to perform an SEO Audit:

You just need to pick the Site Manager tool and then click on SEO Audit for an easy way to do an audit that will give you all the information that you require.

Wrapping Up

In this article, we tried to list the most common SEO mistakes you should be aware of. Of course, there were a few we didn't cover as thoroughly, mainly because you can find them in other articles in this blog.

If you have any questions, feel free to ask away in the comment section or you can find us on Facebook, Twitter, and LinkedIn.