CPM Calculation: Complete Guide with Formulas & Converters

Master CPM calculation with our comprehensive guide. Learn exact formulas, conversion methods, and how to calculate eCPM, vCPM, and other impression-based metrics.
CPM Calculator & Converter
Calculate CPM and convert between different advertising metrics

Input Your Campaign Data

Calculated Metrics

$2.00
CPM
0.50%
CTR
$0.40
CPC
2.00%
CVR
Essential CPM Formulas

1. Basic CPM Formula

CPM = (Total Ad Spend ÷ Total Impressions) × 1000

The fundamental formula for impression-based pricing

Example: $250 spend ÷ 125,000 impressions × 1000 = $2.00 CPM

2. eCPM (Effective CPM)

eCPM = (Total Revenue ÷ Total Impressions) × 1000

Normalizes earnings across different pricing models

Example: $500 revenue ÷ 200,000 impressions × 1000 = $2.50 eCPM

3. vCPM (Viewable CPM)

vCPM = (Total Ad Spend ÷ Viewable Impressions) × 1000

Only counts impressions that meet viewability standards

Example: $300 spend ÷ 100,000 viewable imps × 1000 = $3.00 vCPM

4. RPM (Revenue Per Mille)

RPM = (Total Page Revenue ÷ Total Page Views) × 1000

Publisher metric for page monetization

Example: $150 revenue ÷ 50,000 page views × 1000 = $3.00 RPM
Common CPM Calculation Mistakes

Forgetting the × 1000

CPM is per thousand, not per impression

Mixing Gross & Net

Not accounting for fees and discounts

Wrong Impression Count

Using served vs. viewable impressions

Ignoring Frequency

Not considering unique reach vs. total impressions

CPM Calculation Checklist

CPM Optimization Best Practices
1

Track Multiple CPM Types

Monitor gross CPM, vCPM, and eCPM for complete insights

2

Consider Quality Metrics

Balance low CPM with viewability, brand safety, and performance

3

Test Different Formats

Compare CPM efficiency across display, video, and native formats

4

Optimize Frequency Caps

Reduce waste from oversaturation while maintaining reach

5

Leverage Seasonality

Buy inventory when CPMs are lower (Q1, summer months)

Related Tools & Resources

CPM Calculator

Calculate and compare CPM rates

CPM Optimization

Strategies to reduce CPM costs

CPM vs Other Metrics

When to use CPM vs CPC/CPA