Free tools

Free email tools for developers

Find out why mail lands in spam, check and build SPF, DKIM and DMARC records, and look up MX and blocklists. Instant answers, no sign-up.

Start hereWhy is my email going to spam?Send one email, get a 0–10 score and every reason it might land in spam.Run the spam test →

Test a real email

TestEmail spam testSend one email, get a 0–10 score and every reason it might land in spam.AnalyzeHeader analyzerPaste raw headers to see hops, delays and authentication results.

Check your DNS

CheckDeliverability checkerSPF, DKIM, DMARC, MX and blocklists for a domain, in one check.CheckSPF checkerValidate an SPF record and count its DNS lookups against the limit of 10.CheckDKIM checkerLook up a DKIM key by selector and check its length and syntax.CheckDMARC checkerLook up a DMARC record and get every tag explained.CheckMX lookupList a domain's mail servers and check that each one resolves.CheckBlocklist checkerCheck an IP or domain against Spamhaus, SpamCop, SURBL and more.

Generate records

GenerateSPF generatorBuild an SPF record from a checklist, with a live lookup count.GenerateDKIM generatorCreate a DKIM key pair and TXT record in your browser.GenerateDMARC generatorBuild a DMARC record, with every tag explained.

Fix it at the source

Groundmail is a transactional email API on our own mail servers and IP space. Add your domain, publish the records we give you, and every password reset and receipt goes out signed and aligned. Free for 3,000 emails a month.

Start sending free Read the quickstart