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Email Deliverability Tools
Built by a deliverability consultancy, used on real client work every day.
Postbox MX ToolsCheck your email DNSSPF, DKIM, DMARC, BIMI, MX, reverse DNS and a full Domain Health grade for any domain - with plain-English verdicts and copy-paste-ready fixes.Open →Postbox Blacklist CheckAre you blocklisted?Test any domain or IP against 24 blacklists including Spamhaus and Barracuda, from a dedicated resolver that gets answers public tools miss.Open →Postbox DMARC MonitorIs someone spoofing you?Anyone can forge your domain in a phishing email. DMARC stops impersonation - add one DNS record and get a plain-English weekly report of everyone sending as you and what to block. Free forever.Open →Postbox Mailtester (Free Email Deliverability Audit)Score your email /10Send one real email and get a free deliverability audit - a score out of 10 plus SPF/DKIM/DMARC, domain age, Gmail and Yahoo sender-requirement compliance, blacklists, reverse DNS and content, with the exact fixes.Open →Postbox TLS-RPT MonitorIs inbound mail secure?Know when senders cannot reach your mail server securely: a weekly plain-English report on inbound TLS and MTA-STS failures. No login.Open →Postbox Spoof Check (Spoofing & BEC Exposure)Can attackers spoof you?Check whether attackers can send phishing email as your domain. Get an instant A to F spoofing and business email compromise (BEC) exposure grade from your public DNS. Free, no login.Open →
The tools show you what to fix. We fix it for you.
10+ years, 500+ clients - audits, blacklist recovery, cold email infrastructure and ongoing email operations.