FactCheck.org - From site mission statement: "We are a nonpartisan, nonprofit "consumer advocate" for voters that aims to reduce the level of deception and confusion in U.S. politics."
Snopes.com - "Welcome to snopes.com, the definitive Internet reference source for urban legends, folklore, myths, rumors, and misinformation."
Merriam-Webster.com - "For more than 150 years, in print and now online, Merriam-Webster has been America's leading and most-trusted provider of language information."
There are many, many other "fact check" websites out there but most of these are hosted by news organizations or PACs and should not be trusted to be un-biased. Also one should research the topic by reading unfiltered content such as meeting minutes, court logs, peer reviewed papers and other pubished academic papers.
In the end, there is no better fact check than critical thinking skills.
How to Detect Media Bias & Propaganda In National and World News [PDF] - Excerpt: "The logic behind bias and propaganda in the news media is simple and it is the same the world over. Each society and culture has a unique world view. This colors what they see and how they see it. News media in the cultures of the world reflect the world view of the culture for which they write. But the truth of what is happening in the world is much more complicated than what appears to be true in any culture. To be a critical reader of the news media in any society, one must come to terms with this truth and read accordingly. Critical thinking is a complex set of skills that reverses what is natural and instinctive in human thought."
CriticalThinking.org - "We seek to promote essential change in education and society through the cultivation of fair-minded critical thinking."
Common Logical Fallacies - "Fallacies are common errors in reasoning that will undermine the logic of your argument. Fallacies can be either illegitimate arguments or irrelevant points, and are often identified because they lack evidence that supports their claim. Avoid these common fallacies in your own arguments and watch for them in the arguments of others."