Free Tools
Free email deliverability tools
11 tools for SPF, DMARC, blocklists, headers, signatures, and more. Built by the Review My Emails team. Most checks run with no signup.
Authentication & DNS
Verify your domain's email authentication setup and DNS records.
DMARC Record Parser
Paste a DMARC TXT record or enter a domain. We pull the policy from DNS and break every tag down into plain English.
DMARC Record Generator
Build a DMARC record in under two minutes. Answer five questions and copy a ready-to-publish DNS entry.
DMARC Record Checker
Look up any domain's DMARC policy. Validates alignment, percentage, and reporting addresses.
SPF Record Checker
Validate any domain's SPF record. Counts DNS lookups against the 10-lookup limit and names the services you include.
MTA-STS & TLS-RPT Checker
Verify your MTA-STS policy file and TLS reporting setup. Catches both DNS and policy issues.
Reputation & Monitoring
Watch your sending reputation and decode what is happening inside a message.
Email Blacklist Checker
Check your domain or IP against the major blocklists (Spamhaus, Barracuda, SpamCop, and more).
Email Header Analyzer
Paste raw headers or upload an .eml file and see every authentication check, hop, and spam score in plain English.
Email Raw Source Analyzer
Paste the full raw message source. We decode routing, auth, tracking pixels, and obvious spam signals.
Content & Design
Test the parts of your email that filters and humans actually read.
Subject Line Tester
Flag spam trigger words, preview rendering across Gmail, iPhone, and Outlook, and score deliverability impact.
Email Signature Analyzer
Paste your signature HTML. We grade weight, image count, and link density that quietly hurt every send.
Email Accessibility Checker
Check your email HTML against WCAG standards. Alt text, contrast, structure, dark mode.
How this works
What the tools actually check
Every legitimate email you send competes with billions of spam messages for inbox placement. Whether yours lands in the inbox, the promotions tab, the spam folder, or never arrives depends on three layered signals: authentication (does the receiver trust the message came from you), reputation (does your sending domain or IP have a clean record), and content quality (does the message look like something a human would want to read).
The tools on this page check those signals. The authentication tools (SPF, DMARC, MTA-STS) verify your DNS setup. The blocklist and header tools watch your reputation. The signature, source, accessibility, and subject line tools surface the content issues most senders never look at. Run any tool on its own, or pick the one that matches your problem and follow it where the result sends you.
When to use it
Reach for these when something looks off
If your email is being rejected, or Google or Yahoo just warned you about authentication, start with the SPF Checker and the DMARC Checker. If a domain that used to deliver cleanly suddenly drops off a cliff, run the Email Blocklist Checker first to rule out a reputation hit. If a single campaign tanked, the Header Analyzer or the Source Analyzer will tell you which hop swallowed it.
None of these tools require a signup for the result on screen. Some ask for an email so we can send a copy and so we can keep bots and scrapers out. We do not store the bodies you paste beyond the time it takes to render the answer, and we do not sell what you submit. If you would rather skip the audit work yourself, the “Try it deeper” link below opens a full hand-built review.
Email Almanac
Related questions to read next
Each tool surfaces a symptom. The Almanac explains the underlying mechanism so the next time you hit it, you know what to do without the tool.
Want a deeper look?
The tools surface the most common problems first. When you are ready for a full hand-built audit, sign up on Anchor and we will read your data the way experience taught us.
Try it deeper with RME