Zombie MRR Detector

Find subscription accounts that are still paying but haven't logged in for 90+ days. This MRR is at risk of churning. Free, instant.

Format: customer, mrr, last_login_days_ago — one per line. First line may be a header.
Paste your subscription data above to detect zombie accounts.

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Methodology: how this zombie mrr detector works

This free zombie mrr detector tool gives you a quick, no-signup assessment based on the inputs you provide. The methodology behind it is the same one ChurnLens uses in full buyer-side due diligence, just applied to summary inputs rather than a complete revenue ledger. The output is directional — it tells you whether the numbers you have suggest a healthy business or one with structural churn risk — and it is designed to be conservative, erring on the side of flagging potential problems.

The limitation of any summary-input tool is that it cannot detect the patterns that only emerge from customer-level data: zombie accounts, cohort decay curves, concentration in specific logos, and renewal-cliff timing. Those require the full monthly MRR-by-customer ledger that ChurnLens's paid analysis ingests. Use this free tool as a first-pass screen; if it flags anything concerning, the next step is to upload the full ledger for the complete reconstruction.

The formulas and benchmarks used here are transparent and documented across the ChurnLens learn hub. There is no black box — the goal is to give you the same arithmetic a buyer's diligence team would run, in a format you can use immediately.

Results copied to clipboard!
80%
Overpay for Churn
4.2×
Real vs Reported
$340K
Avg Overpayment
23
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