Free for Shopify brands

Email tools that actually tell you something

No fluff. Each tool gives you a specific answer to a specific question about your email program.

Free tools
📝
Live
Subject Line Grader
Grade any subject line in 3 seconds. Get a letter score, 4 sub-scores, spam check, curiosity signals, predicted open rate vs. Klaviyo benchmarks by vertical, 50 proven DTC templates, and 10 AI-rewritten alternates.
Letter grade A–F
4 sub-scores
50 DTC templates
10 AI rewrites
Grade a subject line →
→
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New
Send Time Optimizer
Find the optimal send windows for your vertical and audience. Get 3 ranked time slots with predicted open rates, what to avoid, and a free 30-day send calendar.
3 ranked windows
7 verticals
30-day calendar
Current time graded
Find your best send time →
→
🎯
New
Email Revenue Gap Quiz
8 questions. No Klaviyo key needed. Find out exactly how much revenue your email program is leaving on the table — and which flows to fix first. Get a dollar-specific gap calculation, missing flow analysis, and 3 prioritized recommendations.
8 questions
No API key needed
Dollar gap calculation
Missing flow analysis
3 recommendations
Shareable permalink
Find your email revenue gap →
→