Deliverability checker
Check any domain's SPF, DKIM, DMARC, and MX records in seconds.
Warming up
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Email infrastructure
Free tools
No signup, no email required. Everything runs instantly and nothing you paste is stored.
Check any domain's SPF, DKIM, DMARC, and MX records in seconds.
Validate an SPF record: one record, 10-lookup limit, and a safe ending.
Build a valid SPF record from your senders and IPs, with the lookup count.
Look up a DKIM key by selector and check its type, size and test mode.
Look up a DMARC policy, reporting address, pct and alignment.
Build a DMARC record, starting at p=none with reports, in plain words.
List a domain's mail servers in priority order and spot a missing or null MX.
Check a BIMI record's logo and certificate links, and whether DMARC is enforced.
Check a domain or mail server IP against Spamhaus, SURBL, URIBL and more.
Scan a subject line and email body for spam-trigger phrases.
Get a day-by-day sending ramp schedule for a new or existing mailbox.
Check text-to-HTML ratio, images, links, and tracking pixels in an email.
Free with an account
Send your domain's daily DMARC reports to Warmerly and see every sending source and whether it passes SPF, DKIM and DMARC, instead of opening XML attachments. Up to 10 domains.
Start with the deliverability checker: if your domain is missing SPF, DKIM, or DMARC, nothing else you change to the email itself will fix inbox placement. If one record is the problem, the SPF checker and DMARC checker go deeper on it, and the blacklist checker tells you whether the domain or its mail server is listed anywhere that matters. Once authentication passes, run the warmup calculator to work out how fast you can safely ramp a new mailbox, then check the email itself, copy through the spam word checker, markup through the email HTML checker, before you send at volume.
All of them run instantly and none of them require an account. The spam word, warmup, and HTML tools run entirely in your browser; the DNS and blacklist checkers perform live lookups and store nothing.
Emails going to spam, cause unknown. Run the deliverability checker to rule authentication in or out, then the email blacklist checker to see whether the domain or its mail server is listed.
A specific record is failing. The SPF checker counts DNS lookups against the limit of 10, the DKIM checker reads a key by selector, and the DMARC checker reads the policy and reporting address. No record yet? The SPF and DMARC record generators build one, and the MX checker lists where a domain's mail is delivered. The BIMI checker reads a logo record and the DMARC policy it depends on.
A new mailbox or a new campaign. The warmup calculator plans a safe sending ramp, and the spam word checker and email HTML checker review the message itself before you send.
These tools check what is published and what you paste in. They cannot tell you where Gmail or Outlook will file a message, which depends on sender reputation and engagement. For that you need warmup and ongoing monitoring, which is what Warmerly's plans add on top.
Beyond a one-off check
Every tool on this page is a snapshot. DNS records get edited, selectors expire, a registrar migration quietly drops a TXT record, and the next thing you notice is a campaign that stopped replying.
InboxPulse re-runs the same checks daily on every connected mailbox and charts placement per provider, so a change shows up as an alert with a cause attached rather than as a slow, unexplained decline.
InboxPulse monitors SPF, DKIM, DMARC, and MX daily and Warmflow automates warmup, so deliverability stays fixed instead of needing a re-check every time something changes.
