If you have webmaster that would be the easiest option. If do not just google Backlink checker and you will have many from to choice. Some of them offer more choice if you sign up.However for your information any free one will do. Good Luck
You can also use Traffic Travis. This is a free tool that shows you the backlinks to your site, as well as your site's on-page analysis. It also helps with keyword research. Hope that helps. Have a good day!
Traffic Travis is a Compaq software for SEO but you have to install it. I think for online uses Google webmaster tools, ahref, majesticseo, backlinkwatch are very useful for backlink analysis.
you can also use market samurai they now have a module specifically for this purpose. It takes the information from the majestic FRESH index, i.e links from the last 60 days this gives a good link profile. Since the Penguin update links diversity in your anchor text in crucial, you should only have 20% of your link profile for your targeted keyword.
Opensiteexplorer - Probably the best and will show you qaulity and deciding Links with lots of useful metrices and, also its free. Ahrefs- excellent tool for indepth link research - tons of infomration about your links and it shows almost every backlinks you create (high quality to lowest quality ones).Its paid Majestic SEO- Similar like Ahrefs - Good when you need detailed link analysis.Its paid Backlink Watch - Quickest but limited infomration.Try it when you are in hurry to have a basic idea about link profile.Free Link Detective - A handy tool to check types of links you have built.
Lots of online tools to check back link...but I like this one for best : http://tools.seobook.com/general/link-check/
Well, Backlinkwatch.com is very popular, I use it often when I need to check backlinks of my competitors.
the very best Free tool online is push2check (fill in the ending here). Not only will you be able to check backlinks but also get free reporst on everything from site usage statistics, builtwith, etc. Very valuable online resource, espeicialy if working from a shoe-string budget.
Majestic SEO does the job very good for me. Also, you can use Market Samurai. If you have a few bucks to invest, in order to benefit from all the features, you won't regret it.