NDR and GDR: The Two Retention Metrics Every SaaS Investor Watches
Written by Harry Prabandham
Curated by Rubric Financial
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The Formulas
- NDR (Net Dollar Retention) = (Starting MRR + Expansion - Contraction - Churn) / Starting MRR, measured over 12 months for a cohort of customers existing 12 months ago.
- GDR (Gross Dollar Retention) = (Starting MRR - Contraction - Churn) / Starting MRR. Excludes expansion. Maxes out at 100%.
- Both are measured on the COHORT of customers at the start of the period, not on all customers including new ones.
- Both are typically reported on a trailing 12-month basis, recomputed monthly.
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About the author
Harry PrabandhamFounder & CEO
Founder and CEO of StartupCFO. MBA from Wharton, MS in Computer Science, and decades of experience building and advising venture-backed startups.
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