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How to Read Your Website Source Code and Why It’s Important

Underneath all the beautiful images, perfect typography, and wonderfully placed calls to action lies your webpage source code. This is the code your browser turns into delightful experiences for your visitors and customers on a daily basis.

Google and other search engines “read” this code to determine where your webpages should appear in their indexes for a given search query. So, a lot of SEO comes down to what’s in your source code.

This is a quick guide to show you how to read your own website source code in order to make sure it’s properly SEO-ed and, really, to teach you how to sanity check your SEO efforts. I also will go over a few other situations where knowing how to view and examine the right parts of source code can help with other marketing efforts.

Finally, if you’re paying someone to SEO your site, this is a great guide to help you keep tabs on them!

How to View Source Code

The first step in checking your website’s source code is to view the actual code. Every web browser allows you to do this easily. Below are the keyboard commands for viewing your webpage source code for both PC and Mac.


  • Firefox – CTRL + U (Meaning press the CTRL key on your keyboard and hold it down. While holding down the CTRL key, press the “u” key.) Alternatively, you can go to the “Firefox” menu and then click on “Web Developer,” and then “Page Source.”
  • Internet Explorer – CTRL + U. Or right click and select “View Source.”
  • Chrome – CTRL + U. Or you can click on the weird-looking key with three horizontal lines in the upper right hand corner. Then click on “Tools” and select “View Source.”
  • Opera – CTRL + U. You also can right click on the webpage and select “View Page Source.”


  • Safari – The keyboard shortcut is Option+Command+U. You also can right click on the webpage and select “Show Page Source.”
  • Firefox – You can right click and select “Page Source” or you can navigate to your “Tools” menu, select “Web Developer,” and click on “Page Source.” The keyboard shortcut is Command + U.
  • Chrome – Navigate to “View” and then click on “Developer” and then “View Source.” You also can right click and select “View Page Source.” The keyboard shortcut is Option+Command+U.

Once you know how to view the source code, you need to know how to search for things in it. Usually, the same search functions you use for normal web browsing apply to searching in your source code. Commands like CTRL + F (for Find) will help you quickly scan your source code for important SEO elements.

Title Tags

The title tag is the holy grail of on-page SEO. It’s the most important thing in your source code. If you’re going to take one thing away from this article, pay attention to this:

You know those results Google provides when you’re searching for something?

All of those results come from the title tags of the webpages they are pointing to. So, if you don’t have title tags in your source code, you can’t show up in Google (or in any other search engine, for that matter). Believe it or not, I’ve actually seen websites without title tags!

Now, let’s do a quick Google search for the term “Marketing Guides”:

marketing guides search results

You can see that the first result is for the KISSmetrics blog section on marketing guides. If we click on that first result and view the page source code, we can see the title tag:

the title tag

The title tag is designated by the opening tag: <title>. It ends with the closing tag: </title>. The title tag is usually near the top of your source code in the <head> section.

And we can see that the content inside the title tag matches what is used in the headline of that first Google result.

Not only are title tags required in order to be included in Google search results, but Google identifies the words in your title tags as important keywords that they think are relevant to their users’ searches.

So if you want a certain webpage to rank for a particular subject matter, you’d better make sure words that describe the subject matter are in the title tag. To learn more about how keywords and title tags are important in your overall site architecture, check out this post.

Here are some important things to remember about your title tags:

  • Make sure you have only one title tag per webpage.
  • Make sure every webpage on your website has a title tag.
  • Make sure each title tag on your website is unique. Never duplicate title tag content.

Meta Descriptions

Another important part of your webpage’s head section is the meta description tag. This 160 character snippet is free advertising copy that gets displayed underneath your title content in the search engines.

the meta description

I’ve seen hundreds of websites that completely ignore this tag. It’s very easy to find in your source code:

meta description source code

So, check to make sure it’s on all of your webpages. More importantly, check to make sure you’re not duplicating it across multiple pages. Duplicating a meta description tag is not a search engine penalty, but it’s a very big marketing mistake.

A lot of people gloss over the meta description, but you really should put some thought into it because it is read by search engine users. Think about what copy would help pull in more visitors and increase click-throughs.

H1 Headings

H1 headings carry a little on-page SEO weight, so it’s a good idea to check your pages to make sure you are using them properly. For each page on your website, look over the source code to see if you spot this tag:

h1 heading source code

You don’t want more than one set of H1 tags appearing on any given webpage. We recently published an article that says you shouldn’t try to over optimize your H1 headings. And what that boils down to is don’t try to purposely boost your SEO by putting your keyword in the H1 heading. Just use it for what it’s meant for – the biggest heading on the page. On your home page, this might be your value proposition.


If you engage in link building, then checking your backlinks to see if they are nofollowed is a must.

But before I go further, I have to talk a little about what “link juice” is. In the world of SEO, getting another website to link to your site is a great achievement. That link is seen by search engines as an endorsement. Search engines factor in the number of links that point to your site when they are ranking your site in their engines. “Link Juice” is a non-scientific term for the so-called power that the link provides your website or webpage in question.

Nofollows are an attribute that can be coded into a link to stop the link juice from flowing to a website. This is a very common thing you will see in the links present in the comment section of blogs.

To find out if your backlinks are passing link juice, you should check to see if the links have nofollow attributes inside them. If they do, then the link you worked so hard to get isn’t doing much for you since the nofollow attribute basically tells Google to ignore your webpage.

The Nofollow Attribute

It might be a little hard to see in the picture above, but rel=’external nofollow’ is in the anchor link. So, even though a person can click through on the link, no link juice is being passed.

Some people think that Google actually does count some link juice from nofollows, but to be conservative in your backlink counting, you should assume nothing is getting passed.

Alternatively, you may want to “page sculpt” some of your own webpages. Some SEOs believe it’s a good idea to limit what pages you send your internal link juice to so that more important webpages get the majority of the site’s overall link juice. You can do this by nofollowing some of your internal website links. For example, you might want to nofollow all of the links to your privacy policy or other boring / uninteresting pages.

Google will tell you to ignore this practice, and I somewhat agree. It’s kind of a tedious, unnecessary task, and your energy is better spent on creating great content instead.

Image Alt Tags

Empty image alt tags are very common SEO boo-boos. Image alt tags describe what your images are to robotic search engines.

If you run an ecommerce website, you definitely want to make sure your alt tags are filled out. A good idea is to make sure that the product brand name and serial number are in the alt tag description.

image alt tag

Above is a screenshot of an image tag with the alt tag buried inside it.

Now, you don’t want to use alt tags for decorative images. That can be seen as an over optimization and be a penalty. Just make sure you have your alt tags filled out for:

  • Images of Merchandise
  • Diagrams
  • Infographics
  • Your Website Logo
  • Screenshots
  • Photos of Team Members

Verifying That Your Analytics is Installed Properly

One last great reason for checking your source code is to make sure you have Google Analytics or KISSmetrics installed on every webpage of your website.

Checking is very simple. For Google Analytics, just view the source code of your webpages and search for the letters “UA.”

verifying google analytics

If you find an instance where the “UA” is followed by a 7-digit number, then you have confirmed that Google Analytics is installed on that one page. Also, keep track of how many times “UA” shows up on your webpage. Sometimes, your analytics tracking code will be inserted more than once accidentally, which is unnecessary. If that’s the case, you should have your developer remove the extra instances.

For KISSmetrics, look for “_km” to confirm that KISSmetrics is installed on your webpage. It’s also a good idea to check to see if the entire code snippet is present. It’s possible that somewhere along the way the snippet was truncated (either by not copying the entire snippet or by devious gremlins living in your developer’s computer).

Next, you will have to check the remaining webpages on your site to see if your analytics code has been inserted on every page. If you don’t have your analytics tracking code on every page of your website, you’re not getting a complete picture of what’s happening on your site, which kind of makes analytics useless.

This can be a daunting task if you have an enormous website. It even can be impossible to check manually.

I like to use to get a text file of all the URLs my website has within it. This provides me with an inventory checklist which helps to keep track of which URLs might need some extra attention (like having analytics installed on them). It’s also a great tool for being alerted to duplicate content issues and other strange things that might be lurking on a web server.

Even will give you only 500 results for free. You may need to ask your developer to give you a URL inventory so that you have a complete map of your massive website. Additionally, you may want them to create a script or program to perform these checks for you so you don’t have to do them manually.

That’s It!

I hope you found this guide helpful. Feel free to ask me any questions in the comments. I may have missed something. :)

About Kissmetrics

Kissmetrics combines behavioral analytics with email automation. Our software tracks actions of your users across multiple devices allowing you to analyze, segment and engage your customers with automatic, behavior-based emails in one place. We call it Customer Engagement Automation. Get, keep and grow more customers with Kissmetrics.

About the Author: is the Minister of Propaganda at KISSmetrics. Feel free to ask him questions about SEO or site architecture by connecting with him on Twitter (@seanvwork) or Linkedin.

  1. Ramsay Leimenstoll Aug 21, 2013 at 10:57 am

    Thanks for the great breakdown, Sean! Even a marketer like me who has no coding experience can understand exactly how to check up on this stuff (I’d call it “source code vital signs”, perhaps) to be sure we’re not missing or completely bungling and important SEO opportunities. Thanks for writing this.

  2. Excellent and must needed post. One thing which I like to do is check what plugins major sites are doing and it has led to some interesting discovering because many big sites are running on wired and it has improved the efficiency of blogs we work on for our clients.

  3. Hannah Ingham (@hannah_ingham) Aug 21, 2013 at 3:28 pm

    Nice points from a client perspective to help them understand some of the inner workings.

    Another way of checking if the analytics code is on all of the pages on your site is with screaming frog, go to configuration > custom > add the analytics UA code, first with the setting to contains and then again in the box below for does not contain. Click ok and add the URL in the search box. Really helpful if you have a large website.

  4. I never bothers about this before but from now i think i need to take care of what my seo compay does with my source code.
    Thanks :)

  5. Parminder Sahni Aug 22, 2013 at 12:43 am

    i too had never given a thought to same but now feel was ignorant all the time & have to get the details about my website source code…..

  6. Some useful reminders there, thanks for that. On the subject of title tags and duplicate content, can I just pass on a little tip that may be useful?

    I had my title tags set up to include the site name. So each title tag read something like this:

    “ABC Greatest Marketing Site In The World ¦ Keyword A”
    “ABC Greatest Marketing Site In The World ¦ Keyword B”
    “ABC Greatest Marketing Site In The World ¦ Keyword C”

    You get the idea. I imagine most of us have done that. Guess what? Google now sees the “ABC Greatest Marketing Site In The Word ” bit as duplicate content. Not really a problem if you have a 5 article blog, but if you have an ecommerce site with a separate page for each of over 5,000 products as I do then it’s an issue.

    After removing the “ABC Greatest Marketing Site In The Word ” part from the title tag I have noticed a significant increase in rankings for certain keywords. Worth bearing in mind

    • Yeah putting your brand name first in your title tags is usually a bad idea. It makes those pages appear to be similar in nature and thus none of them get much importance. Usually putting your brand name at the end of your title tag works fine.

  7. Excellent tips! Sometimes it’s fun to just open a random webpages source code and see how much they’ve messed up… or is that just me?

  8. Thanks so much for the information, and yes indeed it is very helpful! I love looking at code also, and your article makes it all just a bit more understandable. Saving this page for future reference in my own little private email reference library.

  9. Thanks for sharing this post Sean. There’s no doubt that learning a website’s source code is important especially when double checking your SEO (or the competition’s).

  10. Another advantage to reading source code is it can also let you know if you have problems with your plug-ins. As example, if you look at the source code for this page, you’ll see at the very bottom, this text:

    “WP Super Cache is installed but broken. The path to wp-cache-phase1.php in wp-content/advanced-cache.php must be fixed!”

  11. Excellent article, and easy to understand continue the good work.
    This is why Kissmetrics rock. May I need to reverse engineer Kissmetrics source code to further my SEO effort

  12. I will use this tips to spy on my competitor source code using google crome. :) That’s really cool.


  13. It’s also good to take a look at how bloated or outdated your code is. Older websites can be especially troublesome in this area.

  14. Thanks for a great bit of advice. This is something that I haven’t paid any attention to since I switched to a WordPress site and started using seo plugins. I’ll be checking the source code on my site at the first opportunity to make sure that I’m using the plugin correctly and that its working the way it should.

  15. This has opened my eyes to what information is available on a website.
    This has now enabled me to see what the opposition is up to.

    The other thing I cannot get my head round is keywords, most people are looking for the magic keyword for their website but what does one do if there is no other keywords possible and everyone else is using the only keyword….?

  16. Hristo Vassilev Oct 26, 2013 at 1:52 pm

    To be honest, I have seen enough poorly installed GA codes that just checking that the code ‘is on the page’ is definitely not enough – you really need more rigorous QA. :-)

  17. Hi Sean,
    Somehow I found myself on the source code page of my website and I was a little lost, but coming across this article made it much easier to understand.

    Also, your tip about meta descriptions helped a lot. I know some people do not believe in filling out the meta descriptions, while others say it is a must. I am a newbie to online business, so it can be a little confusing.



  18. I recently found this web guy that had create a new web site for me. He charged me $5000 for this new web page. The $5000 was to include SEO for the site. Well, the site looks pretty good but I am unsure how I would know that there was proper SEO done to my web site?

    I am worry that I have paid for something that isn’t done correctly. If you have any suggestion it would be greatly appreciate. Thank you so much!

  19. Stephanie Riggs Jan 07, 2014 at 1:21 am

    The source code of website contains upon different tags which are very important for search engines as well as to display the website in right way. From search engines point of view XML sitemap, meta tags and alt attributes in images is very important to get high ranking as well as good business standing. Those people who even don’t know about viewing source code can easily get access by following your instructions.

  20. (Mr. Sean Work) Awesome

    Thanks for a such a useful article, this article will help seo beginner as i am.

    Lots of new things i got it and going to use for a my client website.

  21. Great to peruse article yet i need to realize that by what method would we be able to discover the Meta Tags into site source. I am attempting to discover however no any meta tags into site source.

  22. Bhupesh Thapar Oct 13, 2014 at 2:58 am

    Hi, I am trying to figure out best way to market my products (B2B)
    I already have an catalog page with Indiamart.
    Question -1 , can i do something to get better visibility of my catalog page on google
    Question-2 I am getting a website of my own . Lot of google adword companies give me an free (template based) website along with ppc promotion for the same price at which others are giving me a customised website. What should i choose, customised website or template based website with assisted ppc , given both are offered same price

  23. Great Article , I just wonder Why the organic visits decreasing and direct visits increasing ? is the google analytics not installed properly?
    Please if you have an answer let me know.
    you can reach me at Twitter #runappsonpc

    Thanks again

  24. Thanks for the good information. As a non-experienced developer, where I can figure out how to implement suggestions, I do. However, it’s time to hire a developer to correct and enhance-site optimization is long overdue. Enjoy the week.

  25. Is there a way to see the conditional tags and such, it seems they don’t appear in the source code when viewed through browsers. Is that right?

  26. When I try to change any details it will not allow me to, do you have any idea why?

  27. Great article on using page source.

    There has been a change in how page source is displayed in Firefox. It used to be that when you viewed page source, it was the exact page source sent to the browser by the webserver. You could look at a rendered page and the page source the browser received from the server side by side.

    Not anymore. Now, instead, when you view page source in Firefox, Firefox makes a new call to the server to get a new set of page source. As a result, you cannot look at the page source that produced the page rendered in the browser.

    This matters when the data on the web page is constantly updating. The data in the page source does not match the data rendered.

    I have checked with some developers who always seem like they know what they are doing and they agree this is problem. I found a work around, use Chrome instead. But I have a question: What is the rationale for the change in how page source works?

  28. I tried viewing my source code to find out what file to go to so that I could make the font larger at the top of each page.

    I looked in every file I could think of in the editor as well. Still am baffled as to how to find where to make this change. Seems there would be a way to reverse engineer things to find the page you put certain text on but no success for me.

    Would appreciate someone’s expert input.

  29. Hello,
    I have found some websites that have “instensedebate” installed for commenting. But I am unable to find source of comments on some of those websites, how may I? Will you please help me?

  30. Great article. I got to know the importance of checking source codes of a webpage when one of the WordPress plugins installed on my site messed up the title tags and meta tags on all the pages of my WordPress site. I lost all my traffic in a matter of weeks. At first, I thought it got hit by some penalty or something, but later realized all the missing title tags in all the pages of Google SERPs. It was a nightmare. Very useful post. :)

  31. Awesome Article on Source Code, This is a great post for someone new to the industry or planning to get into it. Keep it up..


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