Multi-Currency Invoice Total Converter

Selling across borders raises a small but persistent question: an invoice is in one currency, and somebody needs to see the total in another. It might be your accountant, the customer’s finance team or a client who asks for the price in their own money. The conversion itself is a multiplication, but the details, which rate, what margin, and when to round, decide whether the figures agree. This page does the multiplication and shows where the rounding goes.

What you enter

The invoice currency and the target currency, as three-letter labels such as EUR and USD. The exchange rate, meaning how many units of the target one unit of the invoice currency buys. An optional margin, the percentage a bank or card company takes off the rate. An optional tax rate for tax added to the invoice. And the lines of the invoice, one per line, as a description, a pipe and an amount.

How the conversion works

The effective rate is the rate × (1 − margin). The page adds up the lines, adds tax on the subtotal, and multiplies the total by the effective rate. It also converts each line by itself and adds those up, and shows both results so that you can see whether they agree. The reverse rate, one divided by the effective rate, is given for the opposite direction.

A worked example

The default is a euro invoice with lines of 1,200.00, 180.50 and 320.00, converted to dollars at 1.08. The subtotal is 1,700.50 and, with no tax, the total is 1,700.50. At 1.08 the total converted once is 1,836.54, and the three lines converted separately are 1,296.00, 194.94 and 345.60, which add up to the same 1,836.54. The reverse rate is 0.925926. The second sample is a pound invoice converted to rupees at 104.50 with a 2% card margin and 20% tax on lines of 2,500 and 340.75. The effective rate is 102.41, the subtotal 2,840.75, the tax 568.15 and the total 3,408.90, which converts to 349,105.45 rupees. The reverse rate is 0.009765.

Converting once or line by line

When an invoice shows a converted total, convert the total once: that is the number the customer will be asked to pay. When each line must show its own converted amount, round each line, and accept that the lines may add up to a few cents more or less than the converted total. The page shows the difference so that you can see the gap, and in many invoices it is zero.

Edge cases

An exchange rate of zero or less is rejected. The margin may be between 0 and 50, and the tax between 0 and 100. A line without an amount, or an empty list, gives an error that names the problem. Amounts with commas, such as 1,200, are accepted. Numbers are shown with thousands separators and two decimals, without currency symbols, because the codes you typed label the columns.

Limits

The page does not fetch rates, so it cannot tell you what a currency is worth today or on any past date. It does not know your country’s rules about which rate to use on a tax invoice, or when a gain or loss on conversion must be recorded. Check with your accountant for those, and keep the source of the rate with the invoice.

Related tools

• Invoice Generator produces the invoice that you then convert.
• Payment Gateway Fee Calculator estimates what a processor keeps from the converted payment.
• Proforma Invoice Generator prepares the preliminary invoice for an overseas buyer.
• Percentage Calculator works out a margin or tax share on its own.