How to convert currency
Convert an amount in three steps.
Enter the amount
Type the amount you want to convert.
Choose live or manual
Live mode fills the daily reference rate. Manual mode lets you enter 1 source = ? target from your provider.
Check the inverse
Multiply the result by the inverse rate to confirm you return to the original amount.
What does this tool do?
A currency converter with two modes. Live mode fetches daily reference rates through the NumberPrism edge endpoint; manual mode lets you enter the exact rate from your bank, card or exchange desk. The amount is never sent to the rate provider, and the inverse rate is always shown.
Frequently Asked Questions
Does this converter use live exchange rates?
Live mode uses daily reference rates from an open-access currency API, cached for one hour. These are not transaction rates; switch to Manual to enter the exact rate your bank or exchange desk quoted.
Why does my bank give a different number?
Banks and cards often add a spread or fee to the interbank rate. The rate you enter should be the one your provider will apply.
Can I convert in the other direction?
Yes. Use the swap button to exchange the source and target currencies; the rate is inverted automatically.
Live reference rates, with a manual fallback
Live mode uses daily reference rates fetched through the NumberPrism edge endpoint and cached for one hour. That is useful for budgeting and comparison, but it is not the rate your bank will apply. Switch to Manual when you need the exact quote from a bank, card or exchange desk.
Choose the amount and currency pair. Live mode fills the rate automatically; Manual mode lets you enter “1 source = ? target”. The converter multiplies the amount by the rate and shows the inverse so you can check the return trip.
Rate
The number of target units one source unit buys. A bank quote may include a spread, so it can differ from the interbank rate.
Amount
The sum you are converting. The result is rounded for display but the underlying arithmetic keeps full precision.
Fees
Card and transfer fees are separate. If your provider charges 2%, subtract that from the result or add it to the amount first.
Checking a conversion by hand
Multiply the amount by the rate, then multiply the result by the inverse rate. You should get back to the original amount, apart from rounding. If the two numbers disagree by more than a cent, check that the rate is quoted in the direction you expect. A USD→EUR rate of 0.92 and a EUR→USD rate of 0.92 are very different.
For everyday budgeting, a rounded rate is usually enough. For a large transfer, use the rate your provider will actually apply and account for its fee. The percentage calculator can help with the fee arithmetic.