GRP / TRP Calculator
This calculator solves for Gross Rating Points, Target Rating Points, reach, and frequency in any combination, supporting TV, radio, and OOH media planning contexts. It is built for traditional and integrated media planners who work with broadcast buying metrics alongside digital media and need to present a consistent measurement framework across channels. The tool handles all three calculation directions — solving for GRPs from reach and frequency, solving for reach from GRPs and frequency, and solving for frequency from GRPs and reach.
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Results
How this is calculated
Enter any two of the three variables — GRPs or TRPs, reach percentage, and average frequency — along with your target audience universe, and the calculator solves for the missing variable and converts GRPs into estimated audience impressions.
Every model runs locally in your browser. Nothing you type is sent anywhere.
Frequently asked questions
What is the difference between GRPs and TRPs?
Gross Rating Points measure total campaign delivery as a percentage of the total population, counting all exposures including duplicate exposures to the same person. Target Rating Points apply the same calculation but only to your defined target audience rather than the total population. A campaign delivering 150 GRPs across all adults may deliver only 90 TRPs among adults aged 25 to 54, because the media vehicles used index differently against that demographic. TRPs are more useful for evaluating how effectively media investment reaches the intended audience.
How do I convert GRPs to impressions?
To convert GRPs to impressions, multiply total GRPs by the population of the geographic area covered by the media buy, then divide by 100. For example, 200 GRPs in a market with 1 million people equals 2 million gross impressions. This calculation treats GRPs as a percentage-based summary: 100 GRPs means total exposures equivalent to 100% of the population once, though in practice those exposures are distributed across multiple people with varying frequency.
Are GRPs still used in digital media planning?
GRPs remain standard currency in TV buying and some radio planning, but digital media planning primarily uses impression-based metrics. The ad industry has made several attempts to establish a unified cross-platform GRP metric that includes digital and streaming, with Nielsen One and similar products pursuing this goal. For integrated campaigns, many planners maintain parallel GRP and impression calculations for traditional and digital channels respectively, converting between them for executive reporting.