NumRadar checks whether phone numbers are registered on WhatsApp, so you can choose the channel before a campaign or reminder goes out. Upload a CSV or Excel list and download the results, call the REST API from your own app, let an AI agent check numbers over MCP, or check the numbers on a web page with the Chrome extension. You connect no WhatsApp account. Registered and not registered each use one validation; invalid numbers and failed lookups cost nothing. Plans from USD 9 a month.
