Enter Campaign Inputs
Example Data Table
| Gross Impressions | Audience Size | Viewability | Overlap | Unique Reach | Reach % | Frequency | GRPs | Effective Reach % |
|---|---|---|---|---|---|---|---|---|
| 250,000 | 80,000 | 72% | 18% | 67,358 | 84.20% | 2.19 | 184.50 | 28.15% |
Formula Used
- Viewable Impressions = Gross Impressions × Viewability Rate
- Adjusted Impressions = Viewable Impressions × (1 − Overlap Rate)
- Estimated Unique Reach = Audience Size × (1 − e−Adjusted Impressions ÷ Audience Size)
- Reach % = Unique Reach ÷ Audience Size × 100
- Average Frequency = Adjusted Impressions ÷ Unique Reach
- GRPs = Reach % × Average Frequency
- Effective Reach % = Probability of at least n exposures using a Poisson model with λ = Adjusted Impressions ÷ Audience Size
- Effective CPM = Spend ÷ (Viewable Impressions ÷ 1,000)
How to Use This Calculator
- Enter total gross impressions planned for the campaign.
- Add the total addressable audience size for the targeted market.
- Provide known unique reach if you already have reporting data.
- Set viewability and audience overlap to improve realism.
- Choose an effective frequency threshold, such as three exposures.
- Enter campaign days, spend, CPM, and any frequency cap.
- Press Calculate to place results above the form.
- Use the export buttons to save the calculated output as CSV or PDF.
Frequently Asked Questions
1. What does reach mean in media planning?
Reach is the number of unique people exposed to a campaign at least once. It measures breadth of audience coverage, not repeated exposure volume. Marketers usually review it as a count and as a percentage of the target audience.
2. What does frequency mean?
Frequency is the average number of times reached people saw the message. It is calculated by dividing adjusted impressions by unique reach. Higher frequency may improve recall, but very high levels can waste budget when the same users are overserved.
3. Why are viewability and overlap included?
Raw impressions can exaggerate campaign quality. Viewability removes unseen deliveries, while overlap reduces duplication across channels or placements. Together, they produce a more realistic estimate of usable impressions, reach, and frequency for planning decisions.
4. What are GRPs?
GRPs, or gross rating points, combine reach and frequency into one number. They show total audience pressure delivered by a campaign. A plan with 60 percent reach and 3 average frequency produces 180 GRPs.
5. When should I enter known unique reach?
Enter known unique reach when platform reports or panel data already provide it. Leave the field empty during planning stages, and the calculator will estimate reach from adjusted impressions and audience size using an exposure curve.
6. What is effective reach?
Effective reach estimates how much of the audience received at least a chosen number of exposures, such as three. It helps you judge whether the campaign created enough repetition for recall instead of only counting single, light contacts.
7. Why use a frequency cap?
A frequency cap helps identify waste from repeated exposures beyond your preferred limit. The calculator estimates impressions above the cap, making it easier to rebalance budget toward new users or broader reach.
8. Can this calculator replace platform reporting?
No. It is best for planning, scenario testing, and quick diagnostics. Platform reporting remains the source of truth for delivered outcomes because it uses actual auction, delivery, and attribution data from the live campaign.