Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Foreign currency received
1739.03
Lost to spread and fees
100.97
Total cost (%)
5.49
At mid-market rate
1840.00
Rate spread (%)
3.80
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How to use this
- 1Enter amount to exchange ($).
- 2Enter mid-market rate.
- 3Enter rate you're offered.
- 4Enter transaction fee (%).
- 5Enter flat fee ($).
- 6Read your foreign currency received on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Exchange desks quote a rate worse than the market and then add a fee. This shows the true all-in cost against the mid-market rate.
Worked example
Using the values the calculator loads with:
Inputs
- Amount to exchange: 2000 $
- Mid-market rate: 0.92
- Rate you're offered: 0.885
- Transaction fee: 1.5 %
- Flat fee: 5 $
Results
- Foreign currency received: 1,739.03
- Lost to spread and fees: 100.97
- Total cost (%): 5.49
- At mid-market rate: 1,840
- Rate spread (%): 3.8
What each field means
Inputs
- Amount to exchange ($)
- The amount to exchange used in the calculation, measured in $. Starts at 2000 $ so you have a working example on load.
- Mid-market rate
- The mid-market rate used in the calculation. Starts at 0.92 so you have a working example on load.
- Rate you're offered
- The rate you're offered used in the calculation. Starts at 0.885 so you have a working example on load.
- Transaction fee (%)
- The transaction fee used in the calculation, measured in %. Starts at 1.5 % so you have a working example on load. Accepted range: 0–10 %.
- Flat fee ($)
- The flat fee used in the calculation, measured in $. Starts at 5 $ so you have a working example on load.
Results
- Foreign currency received
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lost to spread and fees
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total cost (%)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- At mid-market rate
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Rate spread (%)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the currency exchange fee calculator work?
Exchange desks quote a rate worse than the market and then add a fee. This shows the true all-in cost against the mid-market rate. The underlying maths is: Received = amount × offered rate − fees
What do I need to enter?
5 values: amount to exchange, mid-market rate, rate you're offered, transaction fee, and flat fee. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the foreign currency received result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Currency Exchange Fee Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/currency-exchange-fee
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/currency-exchange-fee" target="_blank" rel="noopener">Currency Exchange Fee Calculator — RevenueLab</a> (2026).</p>
Source: [Currency Exchange Fee Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/currency-exchange-fee) (2026).