Breitbart News media bias rating is Right.

Breitbart News Network is a politically conservative American news and opinion website headquartered in Los Angeles, California, with additional bureaus in Texas, London and Jerusalem. AllSides currently rates Breitbart's bias as right with a high confidence level, a rating with which a small majority of more than 2000 community members disagree. Although 11 of those members who disagreed gave Breitbart an average bias rating of 46.4, which falls in the range of a center bias, this evidence its AllSides Bias Rating™. According to Pew Research, 79 percent of Breitbart’s audience reported having political views that are right-of-center. 

More on Breitbart 

Breitbart was founded in 2007 by conservative commentator and entrepreneur Andrew Breitbart, initially featuring wire stories and direct links to a number of major international organizations. Since then, Breitbart has developed to include more original content, with website components including BigHollywood.com, BigGovernment.com and BigJournalism.com. Breitbart has been the subject of notable, oftentimes controversial topics, including the ACORN 2009 undercover videos controversy, the firing of Shirley Sherrod, the Anthony Weiner scandal, the “Friends of Hamas” story, the misidentification of Loretta Lynch and reporter Michelle Field’s battery complaints against Donald Trump’s campaign. 

Sources:

Breitbart

Wikipedia: Breitbart 

The AllSides Media Bias Rating reflects the average judgment of the American people.

The AllSides Media Bias RatingTM reflects the average judgment of the American people. We don't use a convoluted mathematical or artificial intelligence model, but instead have regular people representing the broad spectrum of Americans blindly rate the bias of articles. That produces a fair, verifiable bias rating.

This media bias rating was determined using the following levels of bias verification.

Basis of Rating:

Blind Survey
Third Party Data
1
Community Feedback
0
Editorial Review
1
Secondary Research

Confidence Level:

High

Unless otherwise noted, this bias rating refers only to news articles on their web site, not from opinion pieces or what is broadcasted on TV or radio. The opinion writers from the same media source may have different bias ratings, so individual writers often are rated separately.