A free, browser-based DNS checker for cold email senders. Enter a sending domain and it reads MX, SPF, DMARC, and DKIM records live from public DNS (via Cloudflare, Google as fallback), grades MX/SPF/DMARC A–F, and explains in plain language what to fix before launching outreach. The SPF card lists each include and its DNS lookup cost against the RFC 7208 limit of 10. DKIM is checked at 10 common selectors but not graded (a missing key may still exist under another selector). Does not inspect sending IPs, blocklists, spam rates, or copy—correct records support delivery but do not guarantee inbox placement. Lookups run in the browser; nothing is stored on ROI Maximizer\'s servers.

A free email deliverability test and spam checker. Send an email to a test address and get a 0-10 score with a fix plan in under a minute. Checks SPF, DKIM, DMARC, blocklists, content, and Gmail/Yahoo bulk sender rules.