Pop-Up Fact Check

Pop-up fact checks and fun facts on YouTube captions, using your own model and API key.

Pop-Up Fact Check watches YouTube closed captions and pops short cards on the player when someone states a checkable claim. How it works • Reads the video’s caption / timed-text track on youtube.com • Spots checkable claims (and optionally fun-fact moments) • Checks each claim with the AI provider and model you choose • Shows a verdict card (true / false / misleading / unclear / opinion) plus a claim log • Optional web search on the checker, when your provider supports it You bring the key • Supported providers: OpenRouter, xAI, Anthropic, OpenAI, Gemini • API keys stay in this browser (chrome.storage.local) • Caption / claim text is sent only to the provider you pick — there is no Pop-Up Fact Check server Setup 1. Open the extension options 2. Paste an API key for at least one provider 3. Choose extractor + checker models 4. Play a YouTube video that has captions (or open the transcript panel) Notes • Needs captions or an available timed-text track • Verdicts are model-assisted, not guaranteed • Clear cached verdicts anytime from Options • Works on Chrome 111+ Privacy summary: keys and cached cards stay on your device. Transcript excerpts go to your chosen provider. See the privacy policy linked on this listing. Support and privacy contact: mattackerman80@gmail.com Privacy policy: https://mattackerman1.github.io/popup-fact-check-privacy/