Reliably check claims in your browser
Building the most reliable fact checking Chrome extension available
Get StartedFact check any claim instantly
We are trying to accomplish one thing. Reliable and verifiable fact checking inside a web browser
Most fact checking tools just ask an AI model and hope that its right. We dont. Every claim is tied to primary sources, has transparent reasoning and auditable results.
How does Certain work
Set up is really easy and integrated with our dashboard
Step 1
Add the chrome extension
Click add to chrome from the dashboard or from the chrome store
Step 2
Highlight any claim
On any webpage or document in your browser, highlight the text, right click and select verify
Step 3
Get an instant verdict
Certain checks it against reliable sources and shows a verdict with citations.Pricing
Here is what we offer
Find the perfect Certain plan to match your needs
Free
Ideal for casual users who want to fact check simple claims
$0 per month
- Standard AI insight
- Limited sources
- 5 verifications per day
- Email support
Premium
Perfect for people who are studying or need on reliable data in their workplace
$4.99 per month
- All Basic Features
- Premium sources
- 500 verifications/month
- Priority support
Pro
Tailored for people who are studying or need on reliable data in their workplace
$9.99 per month
- All Premium Features
- 1000 verifications/month
- Priority Support
Frequently Asked Questions
Here are some common questions we get asked
How do I check a claim?
With the browser extension enabled on chrome, simple highlight any text on the page and right click and select 'Verify'
How accurate is it?
Certain is built to show its work. We have a database of credible sources that are get checked before any other source. When evidence is thin, mixed or a claim cant be verified for certain, it says 'unverifiable'
Whats the difference between the Free and paid plans?
Free includes 10 verifications per day. Premium includes 500 verifications per month and Pro includes 1,000 per month and they both use more reliable soruces and judging.
What happens when I reach my limit?
On the free plan, your allowance resets every day at 00:00 UTC. For paid plans, it resets at the start of each billing period. When you hit your limit, you will be prompted and can upgrade for more checks straight away
Can I cancel anythime?
Yes. You can cancel or change your plan anytime from the dashboard, and you will keep your full access until the end of your current paid period.
Is my data private?
Certain only processes the specific text that you choose to highlight and verify, it doesnt track your general browsing. We retain all claims and verdicts as a source of truth, so that we can continuosly make our product more reliable.
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