CRAAP stands for Currency, Relevancy, Authority, Accuracy, and Purpose.
JustFacts is just the facts. They evaluate the truthfulness of information: facts, whether something was declared factual 50 years ago or 15 days ago. Their claim is “Your source for reliable research,” and their slogan is “A Resource For Independent Thinkers.”
JF cites who uses their website which includes The Washington Post, The Wall Street Journal, Rush Limbaugh, and The Huffington Post. See https://www.justfacts.com/aboutus.asp#serving
FC is a more relevant source for current news than JF because JF hasn’t determined yet what’s actual fact and what’s not a fact about current news issues.
For example, FC has an article about the FISA court memo released by the House Intelligence Committee, but the JF has no mention of the same memo.
Of the first 10 articles on FactCheck.org, 8 of them are not in favor of President Trump. The most frequent source of information is CNN, with 5 of the first 10 stories citing CNN as the source.
JF cites hundreds of sources of information, as they describe themselves as a source of research compilation.
CNN is a primary source for FactCheck.org, and CNN is anti-Trump, and most of their coverage on CNN is negative on President Trump. CNN only looks at one side.
However, I think NBC looks at both sides, and I haven’t found many citations on FactCheck.org from NBC. The last NBC citation on FactCheck was October 18, 2017; therefore FactCheck isn’t very accurate because they are so one sided.
JustFacts.com has only referenced FactCheck once, and that was to point out an inaccuracy published by FactCheck:
“Based upon Mitt Romney’s 2010 federal tax return, the following organizations published articles claiming that Romney pays a lower federal tax rate than most Americans: PolitiFact, FactCheck.org, CBS News, and Agence France-Presse.    All of these articles failed to account for the burden of corporate income taxes, which fall more heavily on upper-income households.” See https://www.justfacts.com/taxes.asp
I believe the purpose of FactCheck.org is to present one-sided opinions as facts.
I believe the purpose JustFacts.com is to present facts and let people decide for themselves what the truth is.