Net Dollar Retention (NDR) Calculator

Calculate net dollar retention and gross retention from expansion, contraction, and churn within your existing customer base — the metric investors watch most closely.

📈 SaaS Metrics📐 NDR = (starting ARR + expansion − contraction − churn) / starting ARR💼 Business

Starting ARR from existing customers

Expansion ARR (upsell, upgrades)

Contraction ARR (downgrades)

Churned ARR (cancellations)

Please enter valid values.

Formula & Reference

Variable	Symbol	Formula	Units
Net Dollar Retention (NDR) Calculator	—	NDR = (starting ARR + expansion − contraction − churn) / starting ARR	percent

Step-by-Step Examples

Example 1

Strong Retention

Starting ARR 1,000,000, expansion 180,000, contraction 40,000, churn 90,000.

Ending = 1,000,000 + 180,000 − 40,000 − 90,000 = 1,050,000
NDR = 1,050,000 / 1,000,000 = 105.0%
GDR = (1,000,000 − 130,000) / 1,000,000 = 87.0%

✓ NDR 105.0%, GDR 87.0%

Example 2

Best in Class

Starting ARR 2,000,000, expansion 700,000, contraction 50,000, churn 60,000.

Ending = 2,590,000
NDR = 129.5%
GDR = 94.5% — low churn plus strong expansion

✓ NDR 129.5% — excellent

Example 3

Masked Churn

Starting ARR 1,000,000, expansion 400,000, contraction 80,000, churn 270,000.

Ending = 1,050,000, NDR = 105.0%
But GDR = (1,000,000 − 350,000) / 1,000,000 = 65.0%
Healthy-looking NDR conceals severe gross churn

✓ NDR 105.0% but GDR only 65.0%

Real-World Applications

💹

Valuation Driver

NDR is among the strongest predictors of subscription business valuation multiples, often more so than growth rate alone.

🚀

Compounding Growth

NDR above 100% means revenue grows from the existing base even with zero new customers — the defining feature of the best subscription models.

🔍

Product-Market Fit Signal

High expansion revenue indicates customers find increasing value over time, which is a stronger signal than initial conversion.

📊

Investor Diligence

NDR and GDR together are standard diligence metrics, since the pair reveals what either alone can hide.

Common Mistakes to Avoid

⚠️

Reporting only NDR without GDR

Net retention can look healthy while gross churn is severe, if a handful of large accounts expand enough to mask broad losses. Always show both.

⚠️

Including new customers in the calculation

NDR measures only the existing cohort. Including new logos turns it into a growth metric and destroys its meaning.

⚠️

Comparing NDR across business models

Enterprise businesses with seat-based expansion naturally show higher NDR than SMB or consumer subscriptions. Cross-segment comparison misleads.

Frequently Asked Questions

What is net dollar retention? ▾

The percentage of recurring revenue retained from existing customers over a period, including expansion and net of contraction and churn.

What is a good NDR? ▾

Above 100% means the existing base grows on its own. 110 to 120% is strong, and above 130% is generally considered best in class.

What is the difference between net and gross retention? ▾

Gross retention excludes expansion and therefore cannot exceed 100%. It shows how much you keep; net shows how much you keep plus grow.

Why do investors focus on NDR? ▾

Because it compounds. A business with 130% NDR grows substantially without acquiring a single new customer, which is enormously valuable.

Can NDR hide problems? ▾

Yes. A few large expanding accounts can mask widespread churn among smaller customers, which is exactly why gross retention should be reported alongside it.