Canonical Tag and 301 Redirect importance in SEO

here is most common issue in SEO Practices, search engine and website owners that is Canonicalization.

Canonical Tag is the best option for dealing with duplicate content pages.  Canonical Tag passes the same amount of link juice ( PR, PA,DA) to the destination url.

Syntax for canonical tag is <link rel="canonical" href="your destination url" >.

One thing kept in mind that canonical tag put in head section of the web page.

Canonical is used for following instances:

Canonical Tag

1. When dynamic URL generated with every new visit.

its depend upon how a user or visitor goes through your website. these type of instances generally occurs in E Commerce websites.

example of this instance -

Suppose a user come on abc.com  and click on product category1 and then after product sub category

  Finally he would be reached product zzz. 

 url -- http://abc.com?prodcat1?prodcat2=zzz.

in other situation if a user directly comes on zzz product . Then url would be -- http://abc.com?info=zzz

in both example user reached on same product with different url.

in these type of situations we are unable to use 3

01 redirect so we will use canonical tag .

2. Syndicated content- Google announced in 2009 that Cross domain use of canonical tag.

it means if a publisher published its content on different website then use rel tag for this. Reason behind it is that only one version of content is eligible for ranking in SERP.

3. Multiple version of same page

http://example.com

http://example.com/index.php

http://example.com

Above three url's are same for user but crawler consider them three different pages with same content.

So we can use redirect over here like < link rel="canonical" href="http://www.example.com">

Why Canonical tag used instant of 301 server redirect ?

Their is only one reason behind it that is - Canonical Tag pass 99 % Link juice to canonical url but 301 redirect pass approx 90-99 % Link Juice. According to Google use 301 redirect whenever canonical tag is not possible

301 Redirects –

301 Redirect

A 301 redirect is a server side redirect designed for moved from old url to a new URL permanently. 301 redirect passes the link juice between 90-99% to the redirected page, and according to Google, are the best way to move url permanently.

When we will use 301 redirects

1. Moving a website to a New Domain

if you want to move your website to new domain or changaing the structure of URL's then you should be use 301 redirect.

2. Multiple Ways to reach  Homepage

if your website have multiple ways to reached home Page . (common issue with and without www ). for this issue you should use 301 redirect.

example :

http://doesseo.blogspot.com

http://www.doesseo.blogspot.com

in this situation  pick one of these URLs as your preferred destination and use a 301 redirect .

Generally www.doesseo.blogspot.com would be used as  preferred domain .

3. If your website have old products and content , and you will want to move this old product to new one . then you would be used 301 redirect to relevant pages.

 4. When your website or blog have some 404 pages then you would be permanently moved these url to home page or their relevant pages.