Free email marketing tools

SPF record checker

Look up and validate your domain's SPF record, with a plain-English verdict.

DMARC record checker

Look up your domain's DMARC record and see whether it actually blocks spoofing.

MX record checker

Look up a domain's mail servers and confirm it's set up to receive email.

DKIM record checker

Look up a DKIM selector and confirm your signing key is published correctly.

Spam word checker

Scan your subject and copy for trigger words and patterns that raise spam risk.

Calculators

Email marketing ROI calculator

Estimate the revenue and return on investment your email program can generate.

Email metrics calculator

Turn raw send counts into delivery, open, click, CTOR and unsubscribe rates.

A/B test significance calculator

Check whether the difference between two email variants is statistically real.

Email list growth calculator

Project your subscriber count over time, factoring in monthly additions and churn.

Utilities

Utility

UTM link builder

Build clean, tagged campaign URLs so every click shows up correctly in your analytics.

Utility

Subject line tester

Score a subject line on length, spam triggers, caps and more before you hit send.

Utility

HTML email size checker

Measure your email's HTML weight and see if Gmail will clip it at 102 KB.