Updated · Methodology: named formula library
CPM/CPC/CPA Conversion
Convert between cost-per-mille, cost-per-click, and cost-per-acquisition metrics.
Spend to Volume = 1:100 (0 as decimal).
CPM, CPC, CPA
- CPM = (spend / impressions) × 1,000
- CPC = spend / clicks
- CPA = spend / acquisitions
Ad benchmarks: CPM $5–$30, CPC $0.50–$5, CPA $20–$200 depending on industry.
Worked Example
1000 Spend to 100000 Volume
- a
- 1000
- b
- 100000
- Result
- 1:100 (0.01)
1000 / 100000 = 0.01. Simplified: 1:100.
When to Use This Calculator
- Compare ad campaigns
- Set bid ceilings
Limitations & Common Mistakes
- Results are estimates based on the inputs you provide.
- Always verify with current data and consult a professional for major decisions.
Frequently Asked Questions
How is the CPM/CPC/CPA Conversion computed?
Spend divided by Volume, plus a simplified ratio (e.g., 4:3) using greatest common divisor. Both decimal and ratio forms are useful in different contexts: decimal for math, ratio form for comparisons or recipe scaling.
What does Spend:Volume mean?
It's a comparison: for every Volume unit, you have a corresponding amount of Spend. Useful when the absolute numbers matter less than the proportion (e.g., reading 8:1 LTV/CAC immediately tells you the unit economics are healthy without needing the dollar amounts).
Why simplify the ratio?
4:3 is more readable than 200:150. The simplified form (using greatest common divisor) preserves the proportion while making it easier to interpret. Common simplified ratios: 16:9 (widescreen), 4:3 (legacy displays), 3:1 (LTV:CAC for SaaS).
When is a ratio more useful than the absolute values?
Comparison across scales. A $1B company and a $1M company can both have a 3:1 LTV:CAC; the ratio reveals comparable unit economics regardless of scale. Use ratios for benchmarking; use absolute numbers for budgeting.
Related Calculators
More Business →YouTube RPM Calculator
Estimate your YouTube channel revenue from RPM (revenue per 1,000 monetized views).
Patreon Tier Revenue Calculator
Estimate Patreon revenue from tier mix and subscriber count.
TikTok Creator Fund Estimator
Estimate TikTok Creator Fund revenue from 1M views ($0.02–$0.04 per 1k views).
Brand Deal Pricing Calculator
Estimate sponsorship rates from follower count using the standard CPM benchmark.
Substack Newsletter Revenue Calculator
Estimate Substack MRR from paid subscribers and conversion rate.
Creator Net Margin Calculator
Calculate your true take-home rate after taxes and platform cuts.