---
title: How does Maxio calculate Net Dollar Retention?
url: https://docs.maxio.com/insights/analytics-reports/advanced-subscription-momentum-report/how-does-maxio-calculate-net-dollar-retention
applies_to: Maxio Core
updated: 2026-10-27
---

# How does Maxio calculate Net Dollar Retention?

The Advanced Subscription Momentum report calculates Net Dollar Retention by comparing what a group of customers pays today with what the same customers paid a year ago. A roll-forward built from monthly movements won't produce the same number.

## Scenario

“I rebuilt our Net Dollar Retention in a spreadsheet by starting with the opening balance and adding a year of expansion, contraction, and losses. I get 193%, but the Advanced Subscription Momentum report shows 185%. Which is right, and how do I reproduce Maxio's number?”

## What Net Dollar Retention measures

Net Dollar Retention (NDR) answers one question: for every dollar of recurring revenue you had from customers a year ago, how much do those same customers pay you now? Above 100% means your existing customers are growing faster than they're leaving.

For more on the report's retention sections, see [What You Can Do with the Advanced Subscription Momentum Report](https://docs.maxio.com/insights/analytics-reports/advanced-subscription-momentum-report/what-you-can-do-with-the-advanced-subscription-momentum-report).

## How the report calculates it

The report divides what your existing customers pay now by what they paid a year ago. Both amounts are recurring revenue, measured at the end of the period.

| March 2026 example | Amount |
| --- | --- |
| Recurring revenue a year ago (end of March 2025) | $6,922,175 |
| Same customers' recurring revenue now (March 2026) | $12,776,364 |
| **Net Dollar Retention** | **≈ 185%** |

## Why a roll-forward gives a different number

Starting from an opening balance and adding a year of expansion, contraction, and losses is how the report analyzes revenue movements in its other sections. It isn't how the NDR line is calculated, so the two methods won't match. To reproduce the report's NDR, compare the same group of customers at two points in time, one year apart.

## Pair it with gross revenue retention

Gross Revenue Retention (GRR) ignores expansion and only counts revenue kept or lost. Suppose 100 customers each paid $1,000 a year ago, 10 left, and the rest expanded by $23,000 in total. GRR is 90% and NDR is 113%. Running both side by side shows whether growth is hiding a churn problem.

> Both metrics cover only customers you already had. New customers added during the year aren't included in either calculation.