AI fact checker: verify claims with sources
Paste an article, essay or post and see whether its claims hold up, with a verdict, a confidence score and the sources behind it.
Trusted by 30k users worldwide
How to fact-check text
- 1
Paste your text
Paste at least 50 words: an article, essay, report or social post.
- 2
Press Verify
Unflag checks the claims in your text against sources on the web.
- 3
Review the verdict
Get a verdict, a confidence score, a short summary, an analysis and links to the sources.
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Why Unflag?
99.5%
Accuracy
Our most advanced model delivers reliable results for essays, research papers, reports and articles.
AI Score
12%
Likely Human-written
Built-in AI detector
See how your text reads to AI detectors before you hand it in.
30k+ users worldwide
Students and professionals around the world use Unflag to write with confidence.
Works in your language
Humanize and rewrite text in English, Spanish, Chinese, Arabic and many more languages.
Every writing tool in one place
Humanize, rewrite, detect and fact-check without switching apps.
Built-in fact checker
Check the claims in your writing against sources on the web.
Works with any AI writer
Paste text from ChatGPT, Claude, Gemini or any other AI. Unflag makes it sound human, so it gets past AI detectors like GPTZero and Turnitin.
Ready wherever you are
Humanize, rewrite and check your writing on your phone with the Unflag app for iPhone and Android.
Simple Pricing
One plan with every tool. Cancel anytime.
Unflag Plus
$3.83/month
$45.99 billed yearly
- Unlock All Features
- Make AI Text Indistinguishable from Human
- Professional Grade AI Detection
- Instant Fact Checking for Total Credibility
- Prevent Hallucination
- 45x More Usage Capacity
- Higher Word Count
- Ad Free, Distraction-Free Experience
Frequently Asked Questions
Can't find your answer? Contact us.
Is the fact checker free?
The fact checker is part of Unflag Plus. Sign in and upgrade to check texts of up to 10,000 characters.
What verdicts can it give?
True, false, partially true, misleading or unverifiable, with a confidence score and the sources it used.
Where do the sources come from?
Unflag searches the web for sources about your claims and links them in the result, so you can read them yourself.
Can I rely on it completely?
Use it as a fast first check. It can miss context or very recent news, so open the sources and confirm important facts yourself.
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