Email A/B Testing: What to Test and How to Read Results
A practical guide to A/B testing emails — what to test, how big a sample you need, and how to avoid fooling yourself.
Email A/B testing replaces opinions with data. Send two variants to small slices of your list, let the winner emerge, then send it to everyone else.
What to test
- Subject line — the highest-leverage variable.
- CTA — wording, color, placement.
- Send time — morning vs evening.
- From name — person vs brand.
Test one thing at a time
Change a single variable per test, or you will not know what moved the result. Stack learnings across many tests instead of guessing with multivariate chaos.
Send email that actually lands in the inbox
API and visual editor, SPF/DKIM/DMARC out of the box, analytics and warm IPs. Free tier — 200 emails/month, no card required.
Read results honestly
Make sure the sample is big enough that the difference is not noise, and judge on the metric that matters — usually clicks or conversions, not inflated opens.
Built-in testing
Sendersy runs subject-line and content A/B tests and auto-sends the winner. Start free.
Writes about campaigns, segmentation and automation. Ran email programs for SaaS and e-commerce.
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