Top 30 SEO Link Authority Websites Worldwide

At the heart of SEO is the fact that search engines use the quantity, context and quality of links pointing to a web page when ranking it for a keyword. This helps them determine how important the site is and what it's about.

Since links are so important, it's interesting to analyse which websites have the most links. It's particularly interesting to compare link authority data with our perceptions about which sites are more popular, important on the web.

Below is a table ranking the global top 30 websites according to the number of inbound links they have - particularly those with the greatest number of separate domains linking to them.

Theoretically these should have the highest basic SEO authority in the world. On-page content, social media signals and many other factors also affect rankings. But as the world's leading authority sites it's reasonable to expect that the sites at the top of the list should be able to rank in Google for just about anything.

Did you know that Twitter - not Google - has the highest link authority site on the web?

Some of this data might surprise you...

Domain	Linking domains	Overall Links	Description
Twitter.com	1,350,000	116,890,000	Microblogging platform and the world's second most popular social network. Many sites link to their Twitter feed
Google.com	872,000	47,620,000	Google's main homepage
Yahoo.com	452,000	23,280,000	Was the biggest search engine before Google's dominance. Now merging with Bing
Baidu.com	308,000	16,750,000	China's top search engine - China has the world's largest population (more than 4 times more people than USA)
Wordpress.com	211,000	14,340,000	The most popular blogging platform
Blogger.com	210,000	7,280,000	Google's blogging platform
Amazon.com	207,000	5,430,000	Online retailer that began life selling books
Youtube.com	204,000	5,960,000	The most popular video-sharing social network - owned by Google
Bing.com	150,000	3,190,000	Microsoft's search engine and rival to Google
Adobe.com	132,000	4,420,000	Provides Flash for online video and reader software for PDF documents - both are popular and frequently linked to.
Taobao.com	108,000	3,140,000	A leading consumer-to-consumer marketplace
Microsoft.com	102,000	1,679,000	Microsoft global homepage
sina.com.cn	97,081	3,580,000	China's leading web analytics provider
Linkedin.com	88,349	2,720,000	The leading professional networking website
Sohu.com	87,309	3,270,000	Chinese search engine
CNN.com	85,057	2,580,000	The leading global news provider (US-based)
Ebay.com	83,948	2,130,000	The world's most popular auction site (peer-to-peer)
PayPal.com	83,886	2,760,000	The world's most popular peer-to-peer payment system. Websites using PayPal often link to the site
163.com	81,974	3,340,000	Leading Chinese web portal
Apple.com	76,271	1,220,000	Apple homepage
Facebook.com	75,988	2,040,000	Homepage of one of the world's most popular social networking sites
Wikipedia.org	74,819	1,700,000	User-edited (wiki) encyclopedia
Yahoo.co.jp	74,434	2,750,000	Yahoo's Japan homepage
Tumblr.com	63,302	4,390,000	A leading blogging platform
Qq.com	62,995	2,280,000	China's biggest web portal
Google.co.jp	62,483	3,300,000	Google's Japan homepage
Msn.com	58,029	1,520,000	Microsoft Network homepage - used to be the default homepage for Windows computers
Google.de	53,443	1,120,000	Google Germany
BBC.co.uk	46,182	1,100,000	Leading provider of news, entertainment and information - ad free - to the UK and the world. Funded by UK TV owners
Imdb.com	45,887	1,320,000	Movie database

Domains are listed in strict order of authority - with the highest authority sites at the top. Authority is based primarily on the number of linking domains. 10 links from 10 domains typically represent more SEO value than 10 links all from the same domain.

Perhaps most interesting of all is that based on this data Twitter is the most authoritative site on the web. Perhaps this is in part because many businesses and individuals link to their Twitter feed from their website.

Of course SEO is about much more than just links and domain authority - but link-based metrics are among the most important SEO factors and they do tend to correlate well with rankings. Based on the enormity of Twitter's link authority alone, pages on the Twitter.com domain might be expected to rank far better in Google than they actually do, for a wide range of terms. Do tweets simply not represent enough content to rank well? That seems likely and might explain why Wikipedia tends to rank far better than Twitter. (Could Google actually be suppressing Twitter URLs? I've seen other anecdotal evidence that this may indeed be the case and it may be worthy of further research).


Yahoo!
Yahoo! comes third - way ahead of Bing and Facebook - which is also something of a surprise at first. But it's a much older domain. It's been a major part of the web for much longer and at for quite some time was the most popular site on the web.

Baidu

Baidu coming fourth in the link popularity chart is a reminder that China is the next global superpower - soon to overtake the USA to become the world's richest and most economically active nation. If China is emerging as the most important country in the world then Baidu is also becoming the most important search engine in a global context. It's the fourth highest authority in the world according to this data, and I expect it to rise to the top of the list by 2015.

6 Ways Google Robs SEO to Pay PPC

If marketing budgets were diverted from SEO to PPC campaigns then Google would make more money - so could that be a secret objective of theirs? Some disturbing signs hint that it may be - and that Google might be using shady tactics to harm SEO campaigns - and ultimately the whole SEO industry - in order to make more money from Adwords.

Google’s advertising business is showing signs of slowing as CPCs decline and market share is lost. Meanwhile, Facebook continues to forge ever-closer ties with Bing - and the combined power and reach of those two online giants poses a serious and growing threat to Google’s dominance of the search market.

That's the motive explained. Here's the means by which Google appears to be assaulting the SEO industry - and the opportunities it may be exploiting in order to do so.

1. Not Provided Keywords

The SEO industry has seen a dramatic rise in traffic from "Not Provided" keywords - a trend that shows no signs of slowing as Google encrypts ever more search queries. If you work in SEO then you'll find this chart all too familiar.



Google claims they encrypt keywords to protect user privacy - but that's just nonsense because they still provide full keyword data via Google Webmaster Tools! The only real difference is that you can't use that data to measure revenue from SEO. That's a very important difference to Google - because they don't make a penny from SEO, only from their paid ads.

Marketers aren't asking for user data - just clean search query data, the same data seen in Webmaster Tools, just linked to transactions and revenue. So what's the problem? Clearly there is no genuine problem - except that Google may not want people to measure the revenue generated by SEO - as opposed to Google Adwords campaigns.

To make matters worse, search share from tablets and smartphones is growing - and Google compells new users of its Android mobile operating system to log in or register. After which, of course, searches are encrypted and hidden from Google Analytics. The next version of Google's web browser, Chrome 25, will encrypt searches by default. Google may be using its growing strength in the mobile and tablet markets to encrypt even more searches.

2. Fewer organic search results

There have been signs that Google also intends to literally reduce the number of organic search results - so that the balance of visible results would shift in favour of Adwords results. This issue has been covered extensively - notably in this article on SEOmoz.

3. Withdrawing Google data from SEO tools

Google has been systematically investigating providers of SEO ranking software - and forcing them to either stop using Google Adwords data or stop tracking rankings. Some, like Raven Tools, were forced to abandon their rank-tracking facilities - and just offer Adwords data instead. So they have changed from SEO tools to Google Adwords tools. Marketers need both sets of information together in order to track SEO campaigns effectively, but Google doesn't seem to want us to track SEO campaigns effectively. only PPC campaigns. This seemingly sinister activity by Google could put some software companies out of business. Not nice.

4. Larger paid results

Adwords ad extensions and experiments are increasingly crowding out the organic results below them. From sitelinks to phone numbers, map links, images, product lists, star ratings and even lead generation forms, these extensions take up more and more space. For some competitive searches only two or three organic results can be seen below the enormous, screen-hogging Adwords ads.

5. Google Shopping has gone - to Adwords

Just to squeeze a little more activity through Adwords, after many years of offering Google Shopping listings for free the platform was shut down - at least for free/organic search results. Effectively Google Shopping has become an extension of Adwords. Anybody sensing desperation here, on the part of Google? It gets worse.

6. More eye-catching Ads

Google further emphasises its bias towards Adwords results by making paid results far more eye-catching than organic results - and not to improve the overall user experience. Just the Adwords user experience.

• Google Shopping images are only shown in Adwords results
• Star ratings are only shown in Adwords

Google is perfectly capable of displaying product images and star ratings in organic results - indeed, as we have seen, they used to provide free product image ads through Google Shopping, as a separate platform to Adwords. I used to love that about Google. But now those eye-catching, click-through-rate-boosting images are reserved for Google's paying customers. Star ratings have only ever been available in paid ads. That only helps Adwords advertisers - not customers and not Google's users (unless they want to click on a paid ad).


These changes may help Google protect its enormous revenues from paid search - and Google may appear to be in control here. But make no mistake: the brands are in control of the Adwords revenue and they can take it away.

More important, though, is the fact that we the people are in charge of the internet. We decide what succeeds and what fails by making our choice. In the long-term, in my view, these changes will alienate brands and customers alike, leaving Google isolated.

The original Google concept was to give people the best possible search results. That's what people want, not the highest bidder, not intrusive ads. There's the inevitable tension between commercial interests and people. But if history reveals one thing it is that, in the end, the people always win.

Search results dominated by expensive, eye-catching paid results from the biggest brands may crowd out small sellers and prevent new businesses from entering the market. That will only harm the market.

Google is doing things that are bad for most businesses who can't compete with brands. It is doing things that are bad for users, which can only lead to a decline in Google's popularity.

Google knows that competitors like Microsoft, Facebook and Apple are poised to exploit Google's weaknesses over the next few years. Google may look unbeatable right now - but if there's one thing that characterises technology, business and the web, it is constant change.

I smell change in the wind. Change for Google. Change for the search market. And change for the web.