How to convert currency offline when travelling abroad

The short answer

You can convert currencies without an internet connection if you download the exchange rates before you go. A currency converter app that stores the last updated rates keeps working on a plane, in a taxi or in a market with no signal. The numbers are not live, but exchange rates for major currencies usually move by a small fraction of a percent in a day, which is accurate enough to judge a price.

The rest of this guide explains why that works, how to do the sums by hand when you have no app at all, and how to check what you are really being charged.

lightbulb Open your converter once on Wi-Fi before you leave, so it saves fresh rates. Then it works anywhere.

Why offline conversion works well enough

An exchange rate is the price of one currency in another. For widely traded pairs such as the US dollar, euro, pound or Indian rupee, that price changes constantly during the day, but the changes are usually small. A rate saved this morning is normally close to the rate you will see tonight, so converting with stored rates gives you a reliable estimate for shopping, taxis and restaurants.

Where it is less reliable is during major news, in currencies that are tightly controlled or unstable, and for large transfers. For a big payment, such as a hotel deposit or a money transfer, check a live rate when you have a connection.

How to convert by hand with no app

If you cannot use an app at all, a simple method is to work out what one unit of your home currency is worth in the local currency, then scale it. Here is the idea with a made-up rate used only to show the arithmetic.

1. Write down the rate for 1 unit of your home currency, for example 1 home unit = 12 local units.
2. To convert a local price to your currency, divide by the rate: a price of 600 local units is 600 ÷ 12 = 50 home units.
3. To convert your money to local currency, multiply: 50 home units × 12 = 600 local units.
4. For a quick mental check, round the rate to an easy number such as 10 or 12 and keep the exact rate for bigger decisions.

lightbulb Rates in this example are invented to show the method. Always use the current rate for the currencies you are converting.

Mid-market rate versus the rate you actually get

The rate you see on a converter is normally the mid-market rate, the midpoint between what banks buy and sell a currency for. It is the fairest reference price, but it is not usually the rate a shop, card or exchange desk gives you. Providers add a margin, a fee, or both.

That is why a converter is best used as a yardstick: if the rate you are offered is far from the mid-market rate, you are paying a large margin and it is worth asking why or choosing another way to pay.

Pay in the local currency, not your own

When a card terminal or ATM asks whether you want to be charged in your home currency or the local one, it is offering dynamic currency conversion. It looks convenient because you see a familiar number, but the exchange rate behind it is set by the merchant or machine, and it is commonly less favourable than the rate your own card network would apply. Choosing the local currency usually costs less.

You can use your offline converter to compare: convert the local price at the mid-market rate, then compare it with the home-currency price on the screen. The gap is the extra you would be paying.

What to look for in a travel currency converter

All Currency Converter, the free Android app from Robince Studio, covers these points: more than 170 currencies, offline use with the last updated rates, rate history from 7 days to 5 years, a built-in calculator and an interface in 55+ languages.

• Offline mode: it keeps the last downloaded rates so it works with no signal.
• A wide choice of currencies, including smaller ones you meet on trips.
• Fast search by currency name or code, and favourites for the pairs you use most.
• Converting one amount into several currencies at once, handy when you are comparing countries.
• Rate history charts, so you can see whether a rate is unusually high or low before you exchange money.
• A built-in calculator for splitting bills and adding up prices without switching apps.

A simple routine before you travel

1. Open your converter on Wi-Fi at home so it downloads the latest rates.
2. Add the currencies for every country on your trip, plus your home currency, to your favourites.
3. Check the rate history chart for your main currency pair to see where today’s rate sits.
4. Note your card’s foreign transaction fee and your bank’s ATM charges.
5. Refresh the rates again at the hotel Wi-Fi when you arrive.

Frequently asked questions

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