# Marginal Revenue Calculator

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

> The marginal revenue calculator works out the extra revenue from selling one more unit – the change in total revenue divided by the change in quantity – from prices and quantities before and after.

## Inputs

- Initial price
- Initial quantity
- New price
- New quantity

## Results

- Initial total revenue
- New total revenue
- Marginal revenue

## Formula

```
Total revenue = price × quantity
Marginal revenue = (new revenue − old revenue) ÷ (new quantity − old quantity)
```

## Explanation

For a firm in perfect competition marginal revenue equals price. A firm facing a downward-sloping demand curve must cut price to sell more, so marginal revenue is below price.

### How to use the Marginal Revenue Calculator

- **Initial price**
- **Initial quantity**
- **New price**
- **New quantity**

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

### How it works

Enter the price and quantity before and after the change.

### Tips

- Use consistent periods (a year or a quarter) for flow figures and period-end values for balances.
- Average opening and closing balances when a ratio mixes a flow with a stock.
- Benchmark against competitors in the same industry.
- Read the ratio together with others – profitability, liquidity and efficiency tell different stories.

### Common mistakes to avoid

- Using sales instead of cost of goods sold for inventory ratios.
- Mixing gross, operating and net profit.
- Ignoring one-off items that distort a single year.

### Inputs explained

FieldWhat to enterInitial priceAmount in your currencyInitial quantityA numberNew priceAmount in your currencyNew quantityA number

### What each result means

- **Initial total revenue** = [Initial price]×[Initial quantity]
- **New total revenue** = [New price]×[New quantity]
- **Marginal revenue** = ([New total revenue] - [Initial total revenue])÷([New quantity] - [Initial quantity])

### Example values

How the main result changes when **Initial price** changes and everything else stays at the example values above:

Initial priceMarginal revenue10109155920925-4130-9140-191

## Worked example

Inputs — Initial price: $20; Initial quantity: 1,000; New price: $19; New quantity: 1,100.

Results — Initial total revenue = $20,000.00; New total revenue = $20,900.00; **Marginal revenue = $9.00**.

## FAQ

**What is marginal revenue?**
The extra revenue from selling one more unit.

**Why is marginal revenue less than price for a monopoly?**
Selling more requires lowering the price on all units.

**Can marginal revenue be negative?**
Yes, when demand is inelastic and a price cut lowers total revenue.

**What formula does the Marginal Revenue Calculator use?**
Total revenue = price × quantity.


## Sources

- [Corporate Finance Institute – financial ratios](https://corporatefinanceinstitute.com/)