Currency Exchange Rate Calculator Formula
Understand the math behind the currency exchange rate calculator. Each variable explained with a worked example.
Formulas Used
Converted Amount
converted = amount * rateInverse Rate
inverse_rate = rate > 0 ? 1 / rate : 0Reverse Conversion
inverse_amount = rate > 0 ? amount / rate : 0Variables
| Variable | Description | Default |
|---|---|---|
amount | Amount | 100 |
rate | Exchange Rate | 1.25 |
How It Works
How to Calculate Currency Exchange
Formula
Converted Amount = Amount × Exchange Rate
The exchange rate tells you how much of the target currency you get for 1 unit of the source currency. For example, if the USD/EUR rate is 0.92, then $100 USD = 100 × 0.92 = 92 EUR.
Inverse Rate
To convert the other way, use the reciprocal: Inverse Rate = 1 / Rate
Worked Example
Convert 100 units at an exchange rate of 1.25.
- 01Converted = 100 × 1.25 = 125.00
- 02Inverse rate = 1 / 1.25 = 0.80
- 03Reverse conversion = 100 / 1.25 = 80.00
Frequently Asked Questions
How do I use this calculator?
Enter the amount in your source currency and the exchange rate (how many units of the target currency per 1 unit of the source). The calculator shows the converted amount.
Where do I find current exchange rates?
Current exchange rates are available from central banks, financial news websites, and currency exchange services. Rates fluctuate continuously during trading hours.
What is the inverse exchange rate?
The inverse rate lets you convert in the opposite direction. If USD to EUR is 0.92, then EUR to USD is 1/0.92 = 1.087.
Ready to run the numbers?
Open Currency Exchange Rate Calculator