Email Health Check & Deliverability Tools
Enter a domain to check its email configuration, authentication and reputation.
Check your email domain, DNS, SPF, DKIM, DMARC, MX records and blacklist status.
Get an Email Health Score with clear guidance on what to fix.
Popular Email Tools
Start with the tools most people need to diagnose email problems.
Email Authentication Tools
Validate and configure SPF, DKIM and DMARC to stop spoofing and improve deliverability.
Email Deliverability Tools
Find out why emails go to spam and improve inbox placement.
DNS & Email Infrastructure
Look up the DNS records that control where and how your email is delivered.
Compliance & Validation
Ensure your email programs meet global regulations and basic address hygiene.
Email Guides
Learn how to fix deliverability problems, read email headers and secure your domain.
Explore All Tools
Browse by category to find exactly the deliverability, DNS, reputation, or compliance tools you need.
Frequently Asked Questions
Answers about EmailToolBox's free online email testing and deliverability tools.
What is EmailToolBox?
EmailToolBox is a free online suite of email testing and domain diagnostics tools. Without signing up or installing anything, you can test SMTP servers, verify email addresses, analyze email headers, and check DNS, SPF, DKIM, DMARC, MX and blacklist records for any domain.
Is EmailToolBox free and does it require signup?
Yes. Every tool is free to use online and requires no account or registration. Just enter a domain, server, email address, or pasted headers and get instant results in your browser.
How do I check why my emails go to spam?
Start with the email health check or email header analyzer. Paste the full raw headers to see SPF, DKIM and DMARC pass/fail plus the Received routing chain. Fix any failed authentication record or missing DNS entry, then re-test.
Which email tools are included?
SMTP test, email verifier, email header analyzer, SPF/DKIM/DMARC checkers and generators, MX, DNS and blacklist lookups, email health check, deliverability analysis, and more than 60 free online tools.
Can I check MX, SPF, DKIM and DMARC records for a domain?
Yes. Enter your domain in the home search box to run a full email health check that covers MX, SPF, DKIM, DMARC and blacklist status, with a health score and prioritized recommendations.
