CPC WORKED EXAMPLE — YENRA — September 6, 2026
All figures are fictional U.S. dollar examples, not benchmarks or bid advice.
The CSV contains fixed computed values, not live spreadsheet formulas.
Use the following formulas to build your own sheet, with the same cohort,
observation window, customer definition, and cost scope throughout.

Average CPC = ad spending / clicks
Customer conversion rate (decimal) = new customers / clicks
Customer conversion percent = decimal rate * 100
Ad cost per new customer = ad spending / new customers
Contribution before ads = new customers * contribution per customer
Contribution after ads = contribution before ads - ad spending
Ad-only break-even CPC = contribution per customer * decimal conversion rate
Contribution is after relevant variable fulfillment costs; this example
excludes fixed overhead and other acquisition costs, so it is not net profit.
Each customer makes one order. Attributed customers are not necessarily incremental.

A: $1000 / 1000 clicks = $1 CPC; 10 / 1000 = 1%; $1000 / 10 = $100 per customer.
10 * $80 - $1000 = -$200. Break-even CPC = $80 * 0.01 = $0.80.
B: $1000 / 500 clicks = $2 CPC; 20 / 500 = 4%; $1000 / 20 = $50 per customer.
20 * $80 - $1000 = $600. Break-even CPC = $80 * 0.04 = $3.20.
If $30 of the $80 contribution must be retained, acquisition allowance = $50.
$50 * 0.04 = $2 CPC before additional acquisition expense.

CPM example: $10 per 1000 impressions * 100000 impressions = $1000.
At 0.5% CTR: 100000 * 0.005 = 500 clicks; effective CPC = $2.
At 0.25% CTR: 100000 * 0.0025 = 250 clicks; effective CPC = $4.
Effective CPC = CPM / (1000 * CTR as a decimal).

Zero clicks: average CPC and customer conversion rate are undefined.
Zero customers: ad cost per customer is undefined, not zero.
Reject negative counts and mismatched periods; explain fractional attribution.
Changing inputs requires recalculation. Verify real costs and cohort maturity.