Yes Ahrefs is awesome for analyzing links as well as competitor links but it's not free.I have run 3 month premium membership on ahrefs.com and the site is really great for checking backlinks.
Not all sites will be 100% accurate and most will display different results. One of my favorites - ahrefs.com
I have tested so many tools for checking back links Like majesticseo.com, backlinkwatch.com, ahrefs.com. etc.....
You can check on google by typing link:yourdomain dot com. yourdomain will be the domain you want to check backlinks of. This brings results of only few sites and few links. Sometimes it doesn't bring results at all. Other thing that you can do is check backlinks on ahrefs dot com. they have free version that you can use
There are so many back link checking tool. just type "Back link checker" in Google and uses any one of result of the search. Best of Luck
you can check you backlinks by forum of backlinkwatch. It is best forum to check backlinks of your sites. Google webmaster is also a good technique to check backlinks