# GRP Calculator – Gross Rating Points

URL: https://speedycalculator.com/calculators/finance/grp/
Last updated: 2026-10-25

> The GRP calculator works out the gross rating points of an advertising campaign – reach as a percentage of the target audience times average frequency – and the target rating points and cost per point.

## Inputs

- Total target audience
- Audience reached
- Average frequency per viewer
- Campaign cost

## Results

- Reach percentage
- Gross rating points (GRP)
- Total impressions
- Cost per rating point
- Cost per thousand impressions

## Formula

```
Reach % = people reached ÷ target audience × 100
GRP = reach % × average frequency
Cost per point = campaign cost ÷ GRP
```

## Explanation

Gross rating points measure the total exposure a campaign buys: 100 GRPs could mean reaching 50% of the audience twice or 25% four times. Media planners use GRPs to compare TV, radio and outdoor schedules.

### How to use the GRP Calculator – Gross Rating Points

- **Total target audience**
- **Audience reached**
- **Average frequency per viewer**
- **Campaign cost**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the size of the target audience, the number of people reached, the average frequency and the campaign cost.

### Tips

- Use figures for the same period (a month, a quarter or a year) for every input so ratios compare like with like.
- Track the metric over time – the trend usually tells you more than a single value.
- Compare your result with industry benchmarks, which vary a lot between sectors.
- Treat the result as a starting point for a decision, then check the assumptions behind each input.

### Common mistakes to avoid

- Mixing monthly and yearly numbers in the same calculation.
- Using revenue where the formula needs profit (or the other way round).
- Forgetting hidden costs such as taxes, fees, overheads or your own time.

### Inputs explained

FieldWhat to enterTotal target audienceA numberAudience reachedA numberAverage frequency per viewerA numberCampaign costAmount in your currency

### What each result means

- **Reach percentage** = [Audience reached]÷[Total target audience]×100
- **Gross rating points (GRP)** = [Reach percentage]×[Average frequency per viewer]
- **Total impressions** = [Audience reached]×[Average frequency per viewer]
- **Cost per rating point** = [Campaign cost]÷[Gross rating points (GRP)]
- **Cost per thousand impressions** = [Campaign cost]÷[Total impressions]×1000

### Example values

How the main result changes when **Total target audience** changes and everything else stays at the example values above:

Total target audienceGross rating points (GRP)1,000,0002881,500,0001922,000,0001442,500,000115.23,000,000964,000,00072

## Worked example

Inputs — Total target audience: 2,000,000; Audience reached: 900,000; Average frequency per viewer: 3.2; Campaign cost: $150,000.

Results — Reach percentage = 45 %; **Gross rating points (GRP) = 144**; Total impressions = 2,880,000; Cost per rating point = $1,041.67; Cost per thousand impressions = $52.08.

## FAQ

**What is a GRP?**
One rating point equals 1% of the target audience; GRPs add up all exposures.

**What is the difference between GRP and TRP?**
TRPs measure only the specific target group; GRPs may use a broader population.

**How many GRPs does a campaign need?**
Many brand campaigns aim for 100–300 GRPs per flight.

**What formula does the GRP Calculator – Gross Rating Points use?**
Reach % = people reached ÷ target audience × 100.