Moz Q&A is closed.
After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.
Is DOCTYPE important for SEO?
-
Hello fellow Mozzers.
I am just having a brief look at a potential clients website before speaking to them tomorrow and whilst looking at the source I noticed that they don't appear to have a clear definition for their Doctype.
All the have at the top of each page is
I have to admit that Doctypes aren't my strong point but I know that they are normally slightly more descriptive than this.
Can this have any effect on rankings? or is this just an issue for W3C validation?
Thanks

-
If it is an HTML 5 page that should be just fine as it is the HTML 5 doctype tag.
Check out the info here: http://www.w3schools.com/html5/tag_doctype.asp
It might cause trouble with really old browsers, but if they have that going I would hope they have already thought about the reasons for and against using it

EDIT: even better link: http://www.w3.org/TR/html5-diff/#doctype
Got a burning SEO question?
Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.
Browse Questions
Explore more categories
-
Moz Tools
Chat with the community about the Moz tools.
-
SEO Tactics
Discuss the SEO process with fellow marketers
-
Community
Discuss industry events, jobs, and news!
-
Digital Marketing
Chat about tactics outside of SEO
-
Research & Trends
Dive into research and trends in the search industry.
-
Support
Connect on product support and feature requests.
Related Questions
-
I need help in doing Local SEO
Hey guys I hope everyone is doing well. I am new to SEO world and I want to do local SEO for one of my clients. The issue is I do not know how to do Local SEO at all or where to even start. I would appreciate it if anyone could help me or give me an article or a course to learn how to do it. Main question The thing that I want to do is that, I want my website to show up in top 3 google map results for different locations(which there is one actual location). For example I want to show up for
Intermediate & Advanced SEO | | seopack.org.ofici3
online clothing store in new york
online clothing store in los angeles or... Let's assume that we can ship our product to every other cities. So I hope I could deliver what I mean. I'd appreciate it if you could answer me with practical solutions.0 -
SEO Advice for Angular JS
We are changing our homepage (and gradually the rest of the site) to Angular JS.
Intermediate & Advanced SEO | | theLotter
In order not to lose anything in terms of SEO we are implementing Hashbangs + escaped fragment snapshots. Are there any other SEO considerations you think we should have and/or additional elements that we could add to the page to improve it in terms of SEO?0 -
Does having a ? on the end of your URL affect your SEO?
I have some redirects that were done with at "?" at the end of the URL to include google coding (i.e. you click on an adwords link and the google coding follows the redirected link). When there is not coding to follow the link just appears as "filename.html?". Will that affect us negatively SEO-wise? Thank you.
Intermediate & Advanced SEO | | RoxBrock1 -
Domain Alias SEO
We have 5 domain alias of our existing sites
Intermediate & Advanced SEO | | unibiz
All 5 domain alias are domain alias of our main site. It means, all domain alias will have exactly same site and contents
Like Main domain: www.mywebsite.com
DomainAlias: www.myproduct.com, www.myproduct2.com, www.myproduc3.com
And if anybody will open our site www.myproduct.com, it will open same website which I have in primary site what can i do to rank all website without any penalty....i s there any way? This is domain alias of in hosting industry Thanks0 -
How important are sitemap errors?
If there aren't any crawling / indexing issues with your site, how important do thing sitemap errors are? Do you work to always fix all errors? I know here: http://www.seomoz.org/blog/bings-duane-forrester-on-webmaster-tools-metrics-and-sitemap-quality-thresholds Duane Forrester mentions that sites with many 302's 301's will be punished--does any one know Googe's take on this?
Intermediate & Advanced SEO | | nicole.healthline0 -
URL Shorteners. Are they SEO Friendly?
Do URL shortener services like bit.ly act as 301 redirects? I was thinking about utilizing one for longer query based URLs and didn't want to risk losing link juice. Thanks for the insight! Regards - Kyle
Intermediate & Advanced SEO | | kchandler0 -
Subdomains and SEO - Should we redirect to subfolder?
A new client has mainsite.com and a large numer of city specific sub domains i.e. albany.mainsite.com. I think that these subdomains would actually work better as subfolders i.e mainsite.com/albany rather than albany.mainsite.com. The majority of links on the subdomains link to the main site anyway i.e. mainsite.com/contactus rather than albany.mainsite.com/contactus. Having mostly main domain links on a subdomain doesnt seem like clever link architecture to me and maybe even spammy. Im not overly familiar with redirecting subdomains to subfolders. If we go the route of 301'ing subdomains to subfolders any advice/warnings?
Intermediate & Advanced SEO | | AndyMacLean0