How to Tell if a Source Is Credible
Updated November 6, 2026
A source is credible when a qualified author backs up clear claims with evidence you can check. The quickest way to test this is the CRAAP test. It has you look at five things: Currency, Relevance, Authority, Accuracy, and Purpose.
For websites, add one more step. Leave the page and see what other people say about it.
What is the CRAAP test?
The CRAAP test is a list of questions for judging a source. Yes, the name is on purpose. It comes from the Meriam Library at California State University, Chico. Sarah Blakeslee wrote about it in LOEX Quarterly in 2004, and the library has a one-page handout with the full list.
| Letter | Stands for | Ask yourself |
|---|---|---|
| C | Currency | When was it published or updated? Does your topic need recent information? |
| R | Relevance | Does it answer your question? Is it at the right level for you? |
| A | Authority | Who wrote it? Are they qualified to write on this topic? |
| A | Accuracy | Where does the information come from? Is there evidence? Can you confirm it somewhere else? |
| P | Purpose | Why does it exist? Is it meant to inform, teach, sell, entertain, or persuade? |
A source doesn’t need a perfect score. The handout says some checks matter more than others, depending on what you need.
How to use each check
Currency: is it recent enough?
Find the publish date and any update date. What counts as recent depends on your topic. A 1995 article may work fine for a paper on a Civil War battle. It’s probably too old for a paper on phone use.
Relevance: does it fit your paper?
A source can be great and still be wrong for you. Make sure it speaks to your exact question, since a source on the general topic may not help. Then check the level. A site for kids is too basic, and a paper full of advanced math may be hard to use well.
If you wouldn’t feel good citing it in your paper, keep looking.
Authority: who’s behind it?
Search the author’s name. Look for a degree, a job, or past work in this field. Expertise doesn’t always carry over, so a surgeon writing about tax law isn’t a tax expert.
If there’s no author, look at the group behind the page. A site with no real “About” page gives you little to go on.
Accuracy: can you check it?
Good sources show their work. Look for citations, data, or links to the original research. Then pick one claim and see if you can confirm it in another source.
Watch the tone, too. Angry or emotional writing is a warning sign, and so are lots of spelling errors.
Purpose: why does it exist?
Ask who gains if you believe it. A sleep article on a mattress company’s site may be accurate, but the company wants to sell you a mattress. That doesn’t make the article useless. It means you should confirm its claims somewhere else.
Also check whether you’re reading a news report, an opinion piece, or an ad. They can look alike online.
Leave the page and read sideways
A polished website can pass a checklist and still mislead you. Fact checkers handle this by leaving the page to see what others say. This is called lateral reading.
In a 2019 paper, Sam Wineburg and Sarah McGrew describe how 45 people judged websites. The group had 10 professional fact checkers, 10 historians, and 25 Stanford students. The fact checkers left each site quickly and opened new tabs. The historians and students tended to stay on the page, where logos and official-looking web addresses could fool them. The fact checkers reached better conclusions in less time.
You can do the same thing in a minute or two:
- Open a new tab.
- Search the name of the site, group, or author.
- See what other sources say about them. Wikipedia is fine for this step.
- Decide if the source is worth your time.
Mike Caulfield’s SIFT method teaches the same habit in four moves. Stop, Investigate the source, Find better coverage, and Trace claims to their original context.
Red flags to watch for
- No author, no date, or no way to contact anyone
- Big claims with no sources
- Numbers with no clear origin
- Links to “studies” that are broken or lead to the same site
- Citations you can’t find anywhere, which you can test with our guide on how to check if a citation is real
- AI summaries with no link to the original, which you can handle with these tips on using AI for research
If a source fails, don’t try to save it. Try the free source finder from Sourcefox, or go back through these steps for finding sources and look for a better one.
Do .edu, .org, and .gov sites count as credible?
The web address is a clue, and that’s all it is. A .gov site belongs to a government body. A .edu site belongs to a college, but it may host a student’s personal page. Anyone can register a .org site, and plenty of solid news outlets use .com.
Note the address, then run your normal checks.
Is peer review proof that a source is good?
Peer review means other experts read a paper before it was published. That’s a strong sign of quality, and it’s why many professors ask for these sources.
It isn’t proof, though. Papers can still have errors, and some are later retracted. Before you rely on a paper, check its page on the journal’s site for a retraction notice.
Common questions
What are some examples of credible sources?
Good starting points include peer-reviewed journal articles, books from university presses, government reports, and news stories from established outlets. Each one still needs a quick check.
Is Wikipedia a credible source?
It’s a useful place to start, but anyone can edit it. Many professors won’t accept it as a citation. Use its reference list to find sources you can cite.
Can a biased source still be credible?
Yes. Every author has a point of view. An opinion piece can be honest and still argue one side. Use it to show what someone believes, and look for neutral evidence to support the facts.