Ad Spend CPM, CPC & ROAS Calculator — Digital Marketing Tool

Campaign numbers

Used for profit and break-even ROAS. Leave at 100 for lead generation.

Leave a field at 0 if you don’t track it. Metrics that need it will show “–”.

Results

Formulas

CPMSpend ÷ impressions × 1,000
CPCSpend ÷ clicks
CTRClicks ÷ impressions × 100
Conversion rateConversions ÷ clicks × 100
CPASpend ÷ conversions
ROASRevenue ÷ spend
Break-even ROAS1 ÷ gross margin

What do CPM, CPC and ROAS mean?

  • CPM (cost per mille): what you pay for 1,000 ad impressions. Useful for comparing awareness campaigns and platforms.
  • CPC (cost per click): what each visit to your site costs.
  • CTR (click-through rate): the share of people who saw the ad and clicked. A low CTR usually points to weak creative or the wrong audience.
  • CPA (cost per acquisition): what each sale or lead costs you in ad spend.
  • ROAS (return on ad spend): revenue earned for every unit spent. A ROAS of 3× means 3 back for every 1 spent.

Why break-even ROAS matters

A “good” ROAS depends on your margin. If you keep 40% of each sale as gross profit, you need a ROAS of at least 2.5× (1 ÷ 0.40) just to cover the ad cost. A shop with a 70% margin breaks even at about 1.43×. Always compare your ROAS with your own break-even, not with someone else’s.

How to improve your numbers

  1. Low CTR: test new images, headlines and audiences.
  2. Good CTR but low conversion rate: fix the landing page: speed, price clarity, trust signals and a clear call to action.
  3. High CPA: raise average order value with bundles or free-shipping thresholds, or narrow targeting to buyers who convert.