What is the formula for reach from impressions?

Reach = Impressions ÷ Average Frequency. If a campaign delivered 500,000 impressions at an average frequency of 2.5, the estimated unique reach is 200,000 people.

What is average frequency in advertising?

Average frequency is the mean number of times each unique person in your reached audience saw your ad. It is calculated as Total Impressions ÷ Unique Reach. A frequency of 3 means each person saw the ad 3 times on average.

Is this reach figure exact?

No — it is an estimate. Real-world reach depends on audience overlap, targeting, ad platform algorithms, and how "unique" is defined (cookie vs. device vs. logged-in user). Use this as a planning approximation, not a guaranteed delivery figure.

What is a good average frequency?

Effective frequency varies by objective. Brand awareness campaigns often target 3–5 impressions per person. Direct response campaigns may aim for 1–2. Very high frequency (10+) risks ad fatigue and wasted spend.

What does Reach % mean?

Reach % is the estimated unique reach divided by your total target audience size, expressed as a percentage. It tells you what share of the audience your campaign covers. This field is optional — leave it blank if you do not know your audience size.

Impressions to Reach Converter

Name: Impressions to Reach Converter
Availability: InStock
Author: Nham Vu

Enter impressions and frequency to get unique reach, or enter reach and frequency to get total impressions.

Conversion Settings

Conversion Direction

Total Impressions

Average Frequency

Mean number of times each person sees the ad.

Total Audience Size (optional)

Used to calculate Reach % of audience.

Results

Enter values and click Calculate.

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Summary

Enter impressions and frequency to get unique reach, or enter reach and frequency to get total impressions.

How it works

Choose a conversion direction: Impressions → Reach, or Reach → Impressions.
Enter your total impressions (or target reach) and the average frequency.
The tool divides impressions by frequency to get reach, or multiplies reach by frequency to get impressions.
Effective Frequency and Reach % of audience are calculated automatically if you provide total audience size.
Copy any result with one click for use in reports or media plans.

Use cases

Estimate how many unique people a campaign will reach given your impression budget.
Back-calculate how many impressions you need to reach a target audience at a given frequency.
Compare reach efficiency across channels with different average frequencies.
Plan media budgets by pairing reach goals with CPM and frequency assumptions.
Audit post-campaign data — verify reported reach against impressions and stated frequency.
Present audience coverage percentages to clients using total market size.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu