Net Revenue Retention Calculator (NRR) — With Gross Revenue Retention

Background.

Net revenue retention answers one question: taking only the customers you already had, and ignoring every new logo you signed, is that base worth more or less than it was at the start of the period? It is the metric investors reach for first in a subscription business, because it isolates the part of growth that does not depend on sales continuing to win new accounts. Datadog's Form 10-K states the exclusion rule that defines it: current-period revenue "includes any expansion and is net of contraction or attrition over the last 12 months, but excludes ARR from new customers in the current period." Drop that exclusion and you no longer have a retention metric — you have a growth rate wearing its name.

NRR is the one retention figure that can legitimately exceed 100%, and this calculator treats that as an ordinary result rather than an error. Box reported net retention of 102%, 101% and 108% in three consecutive fiscal years; Instructure reported 117%, 109% and 106%. Anything above 100% means expansion from existing customers more than replaced everything lost to downgrades and cancellations, which also means net revenue churn is negative. That state is a genuine competitive advantage — it lets a business grow while standing still on new sales — and a calculator that clamped it at 100% or flagged it as invalid would be worse than useless.

This page reports gross revenue retention beside NRR, because the two come from the same four inputs and reading either alone is misleading. The relationship is exact: NRR = GRR + expansion rate. GRR strips expansion out and asks only how much of the opening base survived, so it can never exceed 100%. That single line of algebra carries the most important warning about the metric. A strong NRR can be produced either by keeping almost everyone or by upselling hard to a shrinking core, and only the GRR figure tells you which. In the default numbers on this page, an NRR of 105% sits on top of a GRR of 87% — a base losing 13% of its revenue a year, held up by an 18% expansion rate. Instructure's filed pair at the end of 2022, 106% NRR against 94% GRR, describes a materially healthier business at almost the same headline number.

The third thing to know before you read the result is that there is no single agreed way to compute NRR, so your number and a public company's headline figure may not be comparable. Three conventions are in active use among filers. Box, Datadog and Instructure use a trailing-twelve-month cohort ratio: current-period revenue from a fixed customer cohort divided by that same cohort's revenue a year earlier. HubSpot computes it monthly — retained subscription revenue over retention base revenue at the start of each month — then weights and annualises those rates. This calculator implements the third: the single-period movement identity, because it is the one you can compute from your own MRR movement report without a cohort warehouse. As Box notes in its own filing, net retention "is an operational metric and there is no comparable GAAP financial measure to which we can reconcile this particular key metric." The SEC's 2020 guidance on key performance indicators consequently asks any company presenting a metric like this to publish "a clear definition of the metric and how it is calculated" — and to disclose it if the method later changes.

Finally, annualising compounds. A monthly NRR of 101% is not a 101% or a 112% annual figure but 112.68%, because 1.01 raised to the twelfth power is 1.1268. HubSpot's filing describes exactly this step. The annualised output on this page is a projection rather than a measurement: it assumes the same net movement rate repeats against each period's new and larger base, which is a strong assumption over twelve months and is why the measured twelve-month figure is always the better one when you have it.

What is net revenue retention calculator?

Net revenue retention (NRR), also called net dollar retention (NDR) or the dollar-based net retention rate, measures the change in recurring revenue from an existing set of customers over a period, excluding revenue from customers acquired during that period. It is computed as the opening recurring revenue plus expansion, minus contraction, minus churn, all divided by the opening recurring revenue. Expansion is upsell, cross-sell and added seats or usage from customers who were already there; contraction is downgrades and seat reductions from customers who stayed; churn is revenue lost to cancellation or non-renewal. Because expansion is added back and has no upper bound, NRR can exceed 100%, and a figure above 100% means the existing base grew on its own. Gross revenue retention (GRR) is the same calculation with expansion removed: opening revenue minus contraction minus churn, over opening revenue. GRR can never exceed 100%, and the difference between the two figures is exactly the expansion rate. Neither metric is defined by any accounting standard — both are operational measures, and public filers calculate them by at least three different methods, so the definition matters as much as the number. This calculator uses the single-period movement identity over a period you select, reports GRR and the expansion and gross churn rates alongside NRR, and gives a compounded annualised figure for monthly and quarterly inputs.

How to use this calculator.

1. 01Choose the period your figures cover. Twelve months is the usual reporting basis and the default; pick one month or one quarter if that is how your movement report is cut.
2. 02Enter the recurring revenue in force on day one of the period, counting only customers you already had. Use ARR for a twelve-month period and MRR for a one-month period so the units line up.
3. 03Enter expansion revenue: upsells, cross-sells, extra seats and usage growth from those same customers. Revenue from customers you signed during the period must be left out — including it converts the metric into a growth rate and inflates it.
4. 04Enter contraction (downgrades and seat reductions from customers who stayed) and churn (revenue from accounts that cancelled or did not renew), both as positive amounts. The formula subtracts them.
5. 05Read NRR and GRR together. NRR alone cannot tell you whether the base is healthy — a high expansion rate can carry a weak core. The gap between the two figures is your expansion rate, reported as its own output.
6. 06Check the net revenue churn figure. If it is negative, expansion beat everything you lost and the existing base grew without new sales.
7. 07Use the annualised figure only as a projection. It compounds the period rate forward on the assumption that it repeats; when you have a measured twelve-month figure, prefer it.

The formula.

Four movements act on one denominator. Starting recurring revenue S is the at-risk base: revenue in force on day one from customers who were already there. Expansion E is added, contraction C and churn Ch are subtracted, and the result is divided by S. Net revenue retention is therefore (S + E − C − Ch) ÷ S, and gross revenue retention is the same expression with E removed: (S − C − Ch) ÷ S. Because all four quantities share the denominator S, two identities fall out and both are reported as outputs. First, GRR = 100% − gross churn rate, where the gross churn rate is (C + Ch) ÷ S — this is the same gross revenue churn the churn rate calculator produces on its revenue basis. Second, and more useful, NRR = GRR + expansion rate, where the expansion rate is E ÷ S. In the default figures on this page: S = $5,000,000, E = $900,000, C = $250,000, Ch = $400,000, so NRR = $5,250,000 ÷ $5,000,000 = 105.00%, GRR = $4,350,000 ÷ $5,000,000 = 87.00%, the expansion rate is $900,000 ÷ $5,000,000 = 18.00%, and 87.00 + 18.00 = 105.00 exactly. The identity also explains the asymmetry between the two metrics: C and Ch are non-negative and cannot exceed S, so GRR is confined to the range 0% to 100%, while E has no upper bound and NRR therefore has none either. Net revenue churn is simply 1 − NRR, which turns negative whenever NRR passes 100%. Annualisation raises the NRR ratio to the power 12 ÷ L, where L is the period length in months: a monthly NRR of 1.01 becomes 1.01^12 = 1.126825030, or 112.68%. On rounding: every intermediate value is carried at full arbitrary-precision decimal width and nothing is rounded until the result is returned. The NRR ratio in particular is never rounded before being raised to the 12/L power — doing so at two decimals would move a monthly 101% figure's annualised result by more than a percentage point.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Instructure Holdings, Inc. — Form 10-K for the fiscal year ended December 31, 2022 (accession 0000950170-23-003203), Item 7 MD&A, "Net Revenue Retention Rate; Gross Revenue Retention Rate": gross revenue retention is calculated "by subtracting downgrades and cancellations over a 12-month period from ARR at the beginning of the corresponding 12-month period for a particular customer cohort and dividing the result by the ARR from the beginning of the same 12-month period." Discloses NRR of 117%, 109% and 106% and GRR of 96%, 95% and 94% at 31 December 2020, 2021 and 2022. The only source consulted that files both definitions side by side. Retrieved 2026-07-29.
2. [2]Datadog, Inc. — Form 10-K for the fiscal year ended December 31, 2020, Item 7 MD&A: "Current Period ARR includes any expansion and is net of contraction or attrition over the last 12 months, but excludes ARR from new customers in the current period." Also defines ARR as monthly run-rate revenue multiplied by twelve and cautions that ARR and MRR "do not represent our revenue under U.S. GAAP". Cited for the new-customer exclusion rule. Retrieved 2026-07-29.
3. [3]Box, Inc. — Form 10-K for the fiscal year ended January 31, 2025, Item 7 MD&A, "Net Retention Rate": "Net retention rate is defined as the net percentage of Total Annual Recurring Revenue (Total ARR) retained from existing customers, including expansion" and "Net retention rate is an operational metric and there is no comparable GAAP financial measure to which we can reconcile this particular key metric." Discloses 102%, 101% and 108% at 31 January 2025, 2024 and 2023 — filed evidence of NRR above 100%. Retrieved 2026-07-29.
4. [4]HubSpot, Inc. — Form 10-K for the fiscal year ended December 31, 2024, Item 7 MD&A, "Net Revenue Retention": calculated "by first dividing Retained Subscription Revenue by Retention Base Revenue in the given period, calculating the weighted average of these rates using the Retention Base Revenue for the period, and then annualizing the resulting rates", where Retention Base Revenue is "Contractual Monthly Subscription Revenue of our Customers as of the beginning of each month." Cited as the filed authority for computing NRR on a monthly base and annualising it. Retrieved 2026-07-29.
5. [5]U.S. Securities and Exchange Commission — Commission Guidance on Management's Discussion and Analysis of Financial Condition and Results of Operations, Release Nos. 33-10751; 34-88094; FR-87, 85 Fed. Reg. 10568 (Feb. 25, 2020), Section II "Key Performance Indicators and Metrics", pp. 10569–10570: a registrant presenting a metric should accompany it with "a clear definition of the metric and how it is calculated", and on changing the method should disclose "the differences in the way the metric is calculated or presented compared to prior periods", the reasons and the effects. Official Federal Register text via GPO govinfo. Retrieved 2026-07-29.
6. [6]Banzai International, Inc. — Form 10-K for the fiscal year ended December 31, 2024, Item 7 MD&A, "Customer Churn %": "Churn % = [# or $ value of] Deactivations / [# or $ value of] Active Customers (Beginning of period)." Consulted as an independent check on the beginning-of-period denominator used here; it covers the loss side only and does not address expansion. Retrieved 2026-07-29.