RANKMYMARKETINGMARKETING INTELLIGENCE FOR THE AI ERA
Strategy tool

Email Subject Line Tester

Grade subject lines for opens and inbox risk.

0 chars · 0 words

Frequently asked

Does this actually predict open rates?

It's a directional grader based on subject-line best practices, spam trigger analysis, and mobile preview length. Real open rates depend on sender reputation, send time, and audience — always A/B test.

How long should a subject line be?

30-50 characters and under 9 words hits most inbox previews on both desktop and mobile without truncation.

Are emojis bad for deliverability?

One relevant emoji is usually fine and can lift opens. Two or more, especially at the start, can raise spam-filter suspicion.

Related free tools

Want the full 34-point marketing score?

Combine technical SEO, AI visibility, and marketing strategy in one score with a prioritized roadmap.

Run the full audit