Introduction Introduction. MailTester.Ninja is a free and easy-to-use email checker that verifies or finds any address. Related AI tools ContactBoost – Chrome Extension 15/09/2024 000 AI Advertising Assistant Beno 22/03/2025 000 AI Content Generator Linked API 01/10/2025 000 AI Data Mining groas 08/08/2025 000 AI Ad Generator Upmail – Chrome Extension 25/09/2024 000 AI Email Assistant Fiber AI – Chrome Extension 24/09/2024 000 AI Customer Service Assistant