Guide to Google ranking factors – Part 10: backlinks

Last week we published the ninth instalment of our complete guide to Google ranking factors.

It concentrated on outbound links and how and why these affect your site’s ranking.

This week, we tackle backlinks.

What is a backlink?

A backlink is link from a third party website, back to your own.

These can also be called ‘inbound’ or ‘incoming’ links.

Why are backlinks important?

As revealed by Andrey Lipattsev, the Search Quality Senior Strategist at Google Ireland, earlier this year, links pointing to your website are one of the top three Google ranking factors.

Backlinks are a vote of confidence that someone outside of your own web property trusts your content and believes it has value. Google weighs up each of these links and assigns the linked-to webpage its own value.

Abstract network connection background.

What does Google look for when it comes to backlinks?

1) The number of referring individual domains linking to your website or webpage is a very important factor in Google’s algorithm.

2) The authority of the website or webpage linking to your site is also key. A few high authority links are far more valuable then many from low quality sites.

This from our own guide to authority websites:

An authority website is a site that is trusted. It’s trusted by its users, trusted by industry experts, trusted by other websites and trusted by search engines.

The more good quality links you have the better.

3) An authority website doesn’t necessarily have to be one of the usual big publishers. If you’re a niche website or blog with high quality, relevant content, you can be as highly regarded as any other source.

4) Backlinks from older websites may be worth more than links from newer sites.

5) Backlinks from relevant sites in your niche will be worth significantly more than ones from irrelevant sites or webpages. Some people believe that links from competitors for the same search position as you are worth more than others too.

6) Links from low-quality sites will do very little for your visibility. If the site practices Black Hat SEO (link-schemes, spamming, doorway pages) then can potentially harm your ranking.

7) Links found within the main body text of a webpage is more valuable than links found in separate plugins or widgets found elsewhere on the page.

8) If a site links to you using the ’nofollow’ meta tag then their website’s authority won’t be passed to you. Some publishers automatically nofollow all external links, which is bad practice. Nofollow links should be reserved for sponsored or paid for links and content you don’t necessarily trust but still want to use as an example.

9) Links from a diverse range of websites is good, many links from a single domain to your site (especially if it’s one of the very sites linking to you) can be seen as spammy.

10) Despite previous assumptions, a link from a 301 redirected page shouldn’t lose any PageRank compared to a link from a non-301 redirected page.

11) Anchor text can affect how Google weighs up links to your site. If linking to your homepage and referring to your brand, anchor text should just say your website or brand name. Links to your homepage that are more descriptive “leading experts in local SEO” can be seen as manipulative, so you want to avoid this.

12) Anchor text to specific webpages on your site should be descriptive (but concise) as possible in order to benefit from the link.

13) Links at the top of a page carry more weight than those further down.

14) Links from longer form, evergreen content (a 1,000+ word article that’s been popular for a long time) will be higher value than short, news-based posts.

15) Although the top-level domain isn’t necessarily considered a factor, some people believe obtaining a link from .edu or .gov domains can carry more weight than others. This may be because these sorts of websites have high authority anyway.

For more chapters in our Google ranking factors series, check out:

Part 9: outbound links
Part 8: internal links
Part 7: site-level signals
Part 6: trust signals, authority and expertise.
Part 5: duplicate content and syndication.
Part 4: content freshness.
Part 3: quality content.
Part 2: keyword relevancy, frequency and Latent Semantic Indexing (LSI).
Part 1: on-page signals such as title tags, H1 tags and meta descriptions.

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