Churn Cost Calculator

The calculator

Most SaaS founders know their monthly churn rate. Few have calculated what that churn rate actually costs them in dollars per year. The Churn Cost Calculator closes that gap — it takes the raw churn percentage and outputs the total annual cost in four components: direct lost MRR, replacement acquisition cost, missed expansion revenue, and compounded growth reduction.

The result is a number that makes churn visceral. “3% monthly churn” is abstract. “Your 3% churn costs you $287,000 per year in lost and unrealized revenue” is not.

The math it does

Inputs:

• Current MRR
• Monthly churn rate %
• Average ARPA
• Customer acquisition cost (CAC)
• Average expansion rate for retained customers (NRR contribution from existing customers monthly)

Component 1: Direct lost MRR (annualized)

Each month, MRR × churn rate exits. Over 12 months, with the MRR base declining slightly (or growing, depending on acquisition):

Monthly churned MRR = active MRR × churn rate Annual churned MRR = sum of monthly churned MRR over 12 months

At $100k MRR and 3% monthly churn, approximately $36,000 in MRR churns in month 1 alone. Annualized, this is the total gross revenue exited.

Component 2: Replacement acquisition cost

Every churned customer must be replaced just to stay flat. The replacement cost is:

Annual replacement CAC = (Annual churned customers) × CAC

Where annual churned customers = (annual churned MRR) ÷ ARPA.

At $36k monthly churned MRR, $200 ARPA, and $800 CAC: 180 churned customers/month × 12 months × $800 = $1,728,000 in replacement acquisition cost per year.

(This is the number that makes founders reconsider where to spend on marketing vs retention.)

Component 3: Missed expansion revenue

Churned customers generate no expansion MRR. The expansion value lost is:

Annual missed expansion = annual churned customers × ARPA × expansion rate × average remaining lifetime

This is the revenue the churned customers would have generated through upgrades and seat additions if they had stayed.

Component 4: Compounded growth reduction

Churn reduces the base on which future growth compounds. The calculator shows the MRR at month 24 with the current churn rate vs with a 1 percentage point churn reduction — the “churn reduction value” that quantifies why investing in retention generates more return than an equivalent investment in acquisition.

The total cost output

The calculator sums all four components and displays:

• Annual direct revenue lost to churn: $_____
• Annual CAC spent replacing churned customers: $_____
• Missed expansion revenue from churned customers: $_____
• 24-month growth reduction vs 1pp churn improvement: $_____
• Total annual churn cost: $_____

Then it frames the question: “How much would you pay to cut your churn rate by 2 percentage points?”

How it’s used as a lead magnet

This calculator is the highest-converting tool in the snapshot for selling the churn recovery module. When a founder sees their actual churn cost number:

1. The emotional response is stronger than any feature description.
2. The SaaS Snapshot’s $1,200 one-time cost is trivially small relative to the annual churn cost for any SaaS over $30k MRR.
3. The follow-up sequence can frame the ROI directly: “Your annual churn cost is $X. The SaaS Snapshot’s churn recovery module costs $1,200 one time. What’s your acceptable payback threshold?”

GHL captures the inputs as custom fields, enabling the follow-up sequence to reference the founder’s specific numbers.

Where it lives in the snapshot

• Standalone tools page — /tools/churn-cost-calculator (white-labeled).
• Churn recovery service page — embedded as a pre-conversion tool.
• Paid ad landing pages — “Calculate your churn cost” as the ad headline, calculator as the landing page.
• Pricing page — as a “calculate your ROI” framing before the pricing table.