Email Health Checker by Beacon

Email Health Checker by Beacon is a free, no-signup tool for checking whether a website's domain has its email authentication set up correctly. Click the toolbar icon on any site and it checks that domain for: SPF — confirms which mail servers are allowed to send email for the domain DKIM — checks for a cryptographic signature that proves mail wasn't altered in transit (checked against common selectors) DMARC — confirms there's a policy in place for handling mail that fails these checks A colored badge on the toolbar icon gives you the at-a-glance result (green = all three found, yellow = partial, red = none found), and the popup shows the detail behind each check. Everything runs directly in your browser using public DNS lookups — there's no account, no sign-up, and no data collected. See our full privacy policy for details. Built by Beacon (optinws.com), a deliverability and inbox-monitoring tool for teams that send email and want to know it's actually arriving.