Planning a Budget From a Reach Goal
Media planning usually starts with a reach goal — how many people or impressions a campaign needs — rather than a dollar figure. Once you have an expected CPM for the platform and audience, the budget needed to hit that reach goal follows directly from the standard CPM relationship.
This is the same math as the CPM calculator's “Total Cost” mode, set up here to start from a reach goal rather than a known cost.
Ad Budget Formula
Multiply target impressions by expected CPM, then divide by 1,000.
Ad Budget = (Target Impressions × Expected CPM) ÷ 1,000
Worked Example
A campaign needs to reach 500,000 impressions at an expected $6 CPM.
Ad Budget = (500,000 × $6) ÷ 1,000 = $3,000
Rearranged, the formula solves for impressions or CPM instead, which is what the other two modes above do:
Target Impressions = (Ad Budget ÷ Expected CPM) × 1,000
Expected CPM = (Ad Budget ÷ Target Impressions) × 1,000
What Affects the Budget You'll Need?
- Platform and format — video, social, and programmatic display all carry different typical CPMs for the same reach goal.
- Audience specificity — narrower, higher-intent audiences usually cost more per thousand impressions than broad targeting.
- Seasonality — CPM rises during high-competition periods like Q4, requiring a larger budget for the same reach goal.
- Frequency goals — planning for multiple impressions per person multiplies the impression target, and therefore the budget, well beyond your audience size.
Ad Budget Calculator FAQ
How do you calculate an ad budget from a reach goal?
Multiply your target impressions by the expected CPM, then divide by 1,000: Ad Budget = (Target Impressions × CPM) ÷ 1,000. Enter your impression goal and expected CPM above to calculate it instantly.
What CPM should I use to plan a budget?
Use your own historical average CPM for the platform and audience you're planning for if you have it; otherwise use a conservative estimate from the platform's reported benchmarks or the average CPM by platform table on the CPM calculator homepage.
How is this different from the CPM calculator's "Total Cost" mode?
It's the same underlying formula. This page is framed specifically around budget planning — starting from a reach goal and an expected rate — while the main CPM calculator is framed around measuring or checking a rate from known cost and impressions.
Should I budget for CPM or CPC campaigns the same way?
No — CPC campaigns depend on clicks, not impressions, so use the ad spend calculator (built on CPC and clicks) instead if your campaign is priced per click rather than per thousand impressions.