See growth trends, engagement insights, and subscriber patterns that Substack's dashboard doesn't show you. Free, private, no signup.
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Growth, engagement, sources - no waiting
See your subscribers split into 5 levels: Superfans, Engaged, Moderate, At-Risk, and Inactive. Substack gives you a hidden 0-5 score. We show you the full picture with counts and percentages.
A single 0-100 score combining engagement, list quality, growth momentum, and revenue performance. Know instantly whether your newsletter is thriving or needs attention.
Identify subscribers showing signs of disengagement before they leave. See how much paid revenue is at risk and get re-engagement suggestions.
A month-by-month heatmap showing which subscriber cohorts stick around and which fade. The kind of analysis platforms like Beehiiv charge $43/month for.
Not just how many subscribers each channel brings, but how engaged they are and whether they convert to paid. Compare Reddit vs Twitter vs Substack recommendations side by side.
Every post ranked by open rate, signups, likes, comments, and a performance score. Find which content drives growth and which falls flat.
Everything runs in your browser. Your CSV data is processed locally using JavaScript. Nothing is uploaded to any server. You can even use this tool offline. We use Plausible Analytics for anonymous page view counting with no cookies and no personal data collected.
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Upload email stats, paid growth, growth sources, traffic, or revenue CSVs.
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Your analytics data is saved in your browser's local storage. It never leaves your device. If you clear your browser data or switch browsers, you'll need to re-upload your CSVs. Use the Export button above to save a backup anytime.