In SEO backlinks are the single most precious resource. That's why website promoters spend most of these time hunting for links. Looking for link sources by hand is no more an option. Whether you wish to research your own link profile or scan the links of your competition you'll need to use backlink checkers for this. That's why backlink checking apps are among the most popular SEO tools.This
To help you in your pursuit of links here's a set of most popular backlink checking tools and software (both free and paid).
1. Yahoo! Site Explorer
The grand daddy of backlink checkers and perhaps the single most popular SEO tool on the planet. Yahoo! Site Explorer is great for running quick checks on sites' ranking profiles. It's free and very straightforward to use: you enter the url of the website you wish to check and Site Explorer generates a set of pages linking to it.
There are options that let you exclude the inner links originating from same domain or subdomain. You can also use advanced search operators such as site:/-site: command to check/exclude links coming from a particular website or all sites with certain TLDs (.coms,.edus, etc.)
Note: Yahoo! Site Explorer allows you to check only 1,000 links per domain regardless of how many backlinks the website actually has.
2. Backlink Watch
Backlink Watch is an on the web backlink checker that can help you not merely see what sites link to a page, but additionally gives you some data for SEO analysis, like the title of the linking page, the anchor text of the link, whether the link is dofollow or nofollow, etc. The tool pulls the set of links from Yahoo! Site Explorer, so don't expect wider or different results.
3. Webconfs
Webconfs offers a collection of free online SEO tools. Two of these are made for backlink research. The initial tool is named Backlink Anchor Text Analyzer. It shows you what pages are linking to a certain domain and using what anchor texts. If there are numerous links on a page you'll see all the anchor texts applied to each page. The second tool is Backlink Summary. It will just what its name suggests - gives you a summary of the domains linking to a page and shows you exactly how many links are on each.
Exactly like Backlink Watch, Webconfs tools may also be powered by Yahoo!, and so the email address details are the same and also limited by 1k links per domain.
4. SEO SpyGlass - Majestic SEO - Linkscape
If you're serious about SEO you need to have even more solid backlink checkers at your disposal that would let you dive deeper into the link index, check more links and gather more data for analysis. That's where tools like SEO SpyGlass, Majestic SEO and Linkscape come in handy. These three tools can dig up a lot more backlinks to a site than some other backlink checkers out there. The difference between them is that Majestic and Linkscape rely independently crawlers and link bases while SEO SpyGlass queries a vast amount of search engines and uses advanced search operators to get more links.
Both approaches have their strong points. Utilizing their own crawlers allows gathering larger amount of backlinks but additionally makes the service more costly both for the business and for the finish user. Plus large data sets are usually harder to analyze and apply of. The search engine based approach of SEO SpyGlass gets you just the links that search engines display causing a bit smaller link profile but you can run unlimited backlink checks at no additional cost and the data you obtain is more actionable.