# CPA Calculator – Cost per Acquisition

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

> The CPA calculator works out the cost per acquisition of an ad campaign – total spend divided by conversions – from clicks and cost per click, and compares it with the value of a customer.

## Inputs

- Number of clicks
- Average cost per click (CPC)
- Attributed conversions
- Profit per conversion

## Results

- Total ad spend
- Cost per acquisition (CPA)
- Conversion rate
- Campaign profit after ad spend

## Formula

```
Total ad spend = clicks × CPC
CPA = ad spend ÷ conversions
Conversion rate = conversions ÷ clicks
```

## Explanation

Cost per acquisition tells you how much you pay in advertising for each customer, lead or sale. A campaign is profitable when the CPA is lower than the profit a customer brings – ideally a third or less of their lifetime value.

### How to use the CPA Calculator – Cost per Acquisition

- **Number of clicks**
- **Average cost per click (CPC)**
- **Attributed conversions**
- **Profit per conversion**

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

### How it works

Enter the number of clicks, the average cost per click and the conversions attributed to the campaign.

### 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 enterNumber of clicksA numberAverage cost per click (CPC)Amount in your currencyAttributed conversionsA numberProfit per conversionAmount in your currency

### What each result means

- **Total ad spend** = [Number of clicks]×[Average cost per click (CPC)]
- **Cost per acquisition (CPA)** = [Total ad spend]÷max([Attributed conversions], 0.000001)
- **Conversion rate** = [Attributed conversions]÷[Number of clicks]×100
- **Campaign profit after ad spend** = [Attributed conversions]×[Profit per conversion] - [Total ad spend]

### Example values

How the main result changes when **Number of clicks** changes and everything else stays at the example values above:

Number of clicksCost per acquisition (CPA)2,00017.713,00026.564,00035.425,00044.276,00053.138,00070.83

## Worked example

Inputs — Number of clicks: 4,000; Average cost per click (CPC): $0.85; Attributed conversions: 96; Profit per conversion: $60.

Results — Total ad spend = $3,400.00; **Cost per acquisition (CPA) = $35.42**; Conversion rate = 2.4 %; Campaign profit after ad spend = $2,360.00.

## FAQ

**What is a good CPA?**
One below the profit each customer brings; benchmarks vary widely by industry.

**How is CPA different from CAC?**
CPA covers advertising for one action; CAC includes all sales and marketing costs.

**How can I lower CPA?**
Improve targeting, ad relevance and landing page conversion.

**What formula does the CPA Calculator – Cost per Acquisition use?**
Total ad spend = clicks × CPC.