Uchecker Reviews 

Written by the company

uChecker is an email list verification service for businesses that send email at scale. The platform checks bulk email lists before you hit send, so your campaigns start from a clean, deliverable address base instead of a pile of dead contacts. The service accepts uploads in .txt and .csv format, with no pre-cleaning required. A single verification job can process up to 9,000,000 addresses, and the engine works through roughly 3,200 addresses per minute. Every address is classified as Good, Bad or Risk, and you get the full SMTP reply from the mail server rather than a flat invalid marker. Addresses that cannot be verified go to the Unknown bucket and are never counted as valid, so the results stay honest. uChecker also ships a 13-tool DNS suite that is completely free and requires no account: SPF record generator, DKIM record generator, DMARC record generator, BIMI record generator, MX lookup, SPF/DKIM/DMARC checkers and validators, MTA-STS and TLS-RPT generators, and an email domain health check. The suite covers the whole mail authentication stack in one place. The platform is available as a web app, a REST API with full documentation, a Telegram bot (@uchecker_bot), and an MCP integration for AI agents, so it fits into most workflows out of the box. To date, the database has processed over 1.4 billion email addresses, with more than 193 million unique addresses checked and over 79 million confirmed valid.See more