What CPA will your ad budget actually buy?

A $100 daily budget sounds like a plan until you do the math on what each customer really costs. This planner turns budget, cost per click, click-through rate and landing page conversion rate into monthly conversions and a true cost per acquisition, then goal-seeks the conversion rate you need to hit your target CPA.

Words on this sheet

  • Cost per acquisition: What you spend, on average, to win one new customer.

Marketing Intermediate Goal Seek free

After you install, this is the model to open.

PPC Campaign Planner

  1. In your spreadsheet, click the Sortia icon in the strip of icons down the right-hand edge. No strip? Click the arrow at the bottom-right to open it. You can also use Extensions, then Sortia, then Open Sortia.
  2. Click Start from a template and put that name in the search box.
  3. Pick the card with that name and click Load this template. It arrives on a new tab with real numbers already in it.

The answer

One click runs goal seek on the cost per acquisition cell and solves for the conversion rate that hits your target.

Cost per acquisition today
$375 per customer at a 1.2% conversion rate
Conversion rate needed
6.0% to hit the $75 target CPA
Monthly profit at defaults
-$2,040 8 conversions on $3,000 of spend
Monthly profit at 6% CR
$1,800 40 conversions on the same $3,000

At a $4.50 average CPC and a 1.2% landing page conversion rate, each new customer costs $375 and a $3,000 monthly budget loses about $2,040. Goal seek shows you need a 6.0% conversion rate to hit the $75 target CPA, which flips the identical spend to roughly $1,800 of monthly profit. That makes this a landing page problem, not a bidding problem: generic home pages convert near 1%, while dedicated landing pages can reach 10% or more.

The model

Six assumptions drive the whole model; every downstream number is CPA = CPC divided by conversion rate wearing different clothes.

Daily ad budget$100
Average cost per click$4.50
Ad click-through rate3%
Landing page conversion rate1.2%
Target cost per acquisition$75
Margin per sale$120

Once it is in your sheet

  1. The model arrives with real numbers in it and runs as it stands, so you can press the button first and understand it second.
  2. Change the numbers to yours. The sheet marks which cells are inputs and which hold formulas, and most labels carry a note explaining the row.
  3. Press the run button at the bottom of the panel. It is labeled for the tool you are in, and the result lands on its own tab, with a written reading of it beside the figures.

Never used Google Sheets? Start here goes the whole way, in seven steps, and assumes nothing.