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Free Email Deliverability Tools
Check your authentication, diagnose your DNS, test your content and generate correct records. 19 free tools built by the Mailsoftly deliverability team.
Verify the DNS records that prove you are allowed to send from your domain.
Look under the hood of your domain: mail servers, name servers and reputation.
Catch the things that send a perfectly authenticated email to spam anyway.
Build correct SPF and DMARC records instead of hand-writing them.
Everyday helpers for campaign senders: verify addresses, build tracking links, ship a professional signature.
A silent SPF or DKIM change can quietly send your emails to spam for weeks before anyone notices. Drop your email and we'll alert you the moment something looks off, so you fix it in minutes, not after a deliverability cliff.
Yes. Every tool on this page is free, with no account, no email gate and no usage limits. They are built and maintained by Mailsoftly, an email marketing platform, and we keep them free because senders who fix their deliverability often become customers later.
They are DNS records that prove your emails are legitimate. SPF lists the servers allowed to send for your domain, DKIM adds a cryptographic signature to each message, and DMARC tells receiving servers what to do when a message fails those checks. Mailbox providers such as Gmail and Yahoo now require all three for bulk senders.
Authentication is only the entry ticket. Spam placement also depends on your sending reputation, list quality, engagement rates and the content itself. Run your copy through the Spam Score Tester and your subject line through the Subject Line Tester, and check whether your domain or IP sits on a blacklist.
Check after any DNS change, after switching email providers, and before any large campaign. Records can also change without you noticing, for example when an IT teammate edits DNS. The free monitoring option on each tool page emails you when your SPF, DKIM, DMARC, MX or NS records change.
Domain checks run a live DNS lookup on our server and we log the queried domain and result to improve the tools. The Email Checker logs only the domain of an address, never the mailbox. The Subject Line Tester, Email HTML Preview, Signature Generator and UTM Builder run entirely in your browser, so nothing you type there leaves your machine.
Mailsoftly handles SPF, DKIM & DMARC automatically. Campaigns, automation, and analytics in one place.
Free to start with your Google Workspace account. No credit card required.
