Facebook Ads CBO Budget Allocation Calculator

How to calculate Facebook Ads CBO calculator?

The calculator converts each ad set's relative performance into an allocation share of the total campaign budget. It uses a performance score for each ad set to distribute budget proportionally.

Key formula: allocated_budget_ad_set = total_campaign_budget * (performance_score_ad_set / total_performance_score)

Using the Facebook Ads CBO calculator calculator: an example

Example values: total budget $1,000; performance scores — Ad Set A: 40, Ad Set B: 30, Ad Set C: 30.

Step-by-step calculation:

1. Sum performance scores: 40 + 30 + 30 = 100.
2. Calculate each ad set share: A = 40/100 = 40%, B = 30/100 = 30%, C = 30/100 = 30%.
3. Multiply by budget: A = 0.40 × $1,000 = $400; B = $300; C = $300.
4. Optional: use allocated budget with your CPC and conversion rate estimates to forecast clicks and conversions.

Frequently Asked Questions

What is a performance score?

A performance score is a numeric measure that reflects an ad set's expected effectiveness, typically derived from metrics like CTR, conversion rate, and cost per conversion.

Can I use historical campaign data for scores?

Yes. Using recent historical CTR, conversion rates, and CPC gives more accurate performance scores and therefore more reliable budget allocations.

How many ad sets should I include?

Include all ad sets you plan to run in the same CBO campaign. Avoid adding very small or untested ad sets, as they can distort allocation when scores are unstable.

Will CBO always improve performance?

CBO helps distribute budget toward higher-performing ad sets but does not guarantee better results. Regular monitoring and updating of performance scores is required to maintain effectiveness.