Zombie MRR Detector

How to use this detector

1. Enter Total MRR — the total monthly recurring revenue across all customers.
2. Enter Inactive-but-Paying MRR — the MRR from accounts that haven't logged in, made API calls, or used seats in 60+ days but are still being charged.
3. Enter Inactive Account Count — how many individual accounts are inactive.
4. Enter Total Customer Count — the total number of paying customers.
5. Click Detect — see your zombie MRR percentage and how it compares to SaaS health benchmarks.

Why zombie MRR matters in SaaS due diligence

Zombie MRR is the silent killer of SaaS valuations. A target company may report 2% monthly churn, but if 18% of their revenue is from customers who haven't used the product in months, that churn number is a ticking time bomb. When those annual contracts come up for renewal, the real churn rate emerges — sometimes 3–5× higher than reported.

Sellers rarely volunteer zombie MRR data. It's the buyer's job to request customer activity logs (login frequency, API call volume, seat utilization) and cross-reference them against billing. The full ChurnLens Zombie MRR Detector automates this from raw CSVs and projects the revenue impact using Annual-Plan Decay Projection.

Zombie MRR benchmarks: how much is too much?

Below 5% of total MRR: Healthy range. Some passive usage is normal, especially for annual-plan enterprise customers who may use the product intensively for a few months and coast the rest of the year (Recurly 2025).

5–15% of total MRR: Elevated. Investigate why these accounts are inactive. Are they seasonal users? Paused projects? Or genuine zombies that will churn at renewal? Cross-reference contract end dates.

Above 15% of total MRR: Concerning. A material portion of reported revenue is at high risk of churning at the next renewal window. Buyers should model this as likely lost revenue and adjust valuation accordingly.