Money and currencies

Amounts of money in a calc block keep their currency, so a shopping list adds up in pounds, a bill splits into euros and a salary converts from a yearly to a monthly figure without losing track of what it’s measured in. This page covers writing amounts, how they’re displayed, arithmetic with money, converting between currencies and working with prices per unit. Reach for it for budgets, bills, invoices, travel spending and anything else with a price on it.

For interest, loans, inflation and tax, see Finance, inflation and tax. For adding VAT, discounts and tips, see Percentages.

Writing an amount

Write money the way you’d see it on a receipt. A currency symbol or three-letter code can go before or after the number, and you can also spell out the currency’s name:

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£12.50 gives £12.50

$1,250 gives $1,250.00

12€ gives €12.00

45 USD gives $45.00

EUR 80 gives €80.00

100 dollars gives $100.00

50 british pounds gives £50.00

100 swiss francs gives CHF 100.00

¥1500 gives ¥1,500

The accepted forms are:

100 US dollars isn’t recognised; write 100 USD or 100 dollars instead.

Currency symbols

Besides $, €, £, ¥ and ₹, Varlig recognises these symbols:

$ on its own means US dollars, so write a$50 or 50 AUD for Australian dollars. Every ISO 4217 code is known, including XAU (gold) and XAG (silver). The currency reference lists them all with their names.

Cents and pence

Write pence and cents the way a price label does, with p or c straight after the number, or spell out pence (also penny and pennies), cents or euro cents. The answer comes out in pounds, dollars or euros, ready to add to everything else:

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99p gives £0.99

45p * 12 gives £5.40

3 * 99c gives $2.97

50 euro cents * 4 gives €2.00

Pounds and pence, or dollars and cents, add up directly, with no exchange rate involved:

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£1.20 + 45p gives £1.65

$4.50 - 75 cents gives $3.75

€2 + 50c gives €2.50

Next to an amount in euros, c and cents mean euro cents, so the last line reads the way you’d say it. To see an answer in the smaller coin, add in pence or in cents:

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45p * 12 in pence gives 540 pence

£1.65 in pence gives 165 pence

24.5p/kWh in pence/kWh gives 24.5 pence/kWh

Energy tariffs, fuel prices and mileage allowances are often quoted in pence, and they work as prices per unit. A price per unit keeps its fractions of a penny, so a tariff matches your bill, and the total you pay comes to the nearest penny, as on a receipt:

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24.5p/kWh gives £0.245/kWh

148.9p/L gives £1.489/L

148.9p/L * 45 L gives £67.01

11,500 kWh * 6.2p/kWh gives £713.00

45p per mile * 120 miles gives £54.00

450 kWh at 28 cents per kWh gives $126.00

p counts as pence after a decimal or a whole number under 100, with no space in between. That keeps other meanings safe: 1080p is still a video resolution. For larger amounts, write 150 pence or £1.50.

c also stands for Celsius, so Varlig lets the rest of the line decide:

• Next to money or before a rate, it’s cents. €2 + 31.5c is €2.32, and 31.5c/kWh is a tariff.
• In a line about temperature, it’s Celsius. 20c in F is 68 °F, and with oven = 180c, oven - 20c is 160 °C.
• Otherwise the number decides. A whole number up to 99 is cents (99c), and a negative number, a decimal or 100 and over is Celsius (180c is 180 °C).

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31.5c/kWh gives $0.315/kWh

2 kW * 3 hours * 31.5c/kWh gives $1.89

20c in F gives 68 °F

180c gives 180 °C

When 20c or 31.5c stands on its own, hold the pointer over it to see which reading Varlig chose and how to write the other one. If you’ve named a value p or c in the note, your name wins, so 5p is five times it.

How amounts are displayed

Most currencies show two decimal places, rounded for display. Varlig keeps the full value behind the scenes, so nothing drifts when you carry an answer into later lines:

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£100 / 7 gives £14.29

£100 / 7 * 7 gives £100.00

share = £100 / 7 gives £14.29

share * 7 gives £100.00

A line that gives the amount a name shows it the same way, and the name keeps the full value for later lines.

Currencies whose smallest coin is a whole unit, such as the Japanese yen and Korean won, show no decimals. Those with a three-decimal minor unit (KWD, JOD, OMR, TND, LYD, IQD) show three. Amounts below a million are shown in full, so a salary or a house price keeps every penny on screen. From a million up, they’re shortened with M and B:

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¥1000 / 3 gives ¥333

10 KWD / 4 gives 2.500 KWD

$250k gives $250,000.00

£99,999.99 * 2 gives £199,999.98

£1,200,000 gives £1.2M

To change how an answer looks, use answer formatting in the line’s context menu, or the formatting options in Settings.

Arithmetic with money

Money in a single currency adds, subtracts, multiplies and divides like any other quantity. Dividing two amounts in the same currency gives a plain number, and percentages work the way you’d say them:

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£45.50 + £12.30 + £8.20 gives £66.00

£2.40 * 3 + £1.80 gives £9.00

£1,200 / 3 gives £400.00

£1,200 / £400 gives 3

£80 + 12.5% gives £90.00

£240 * 20% gives £48.00

$100 - 20% gives $80.00

1.5 kg * £4.80 gives £7.20

In the last line Varlig reads £4.80 as a price per kilogram. It does that whenever a plain amount multiplies a measurement, and it says so: hover over the amount to see a note such as “£4.80 treated as a price per kg”. If the amount is really a total, as in a monthly rent, that note is your cue to check the line. Writing the rate out, £4.80/kg, makes it explicit and the note goes away.

To share a cost by size, multiply by one part and divide by the whole. The measurements cancel, so the answer stays in pounds, or in pounds a month for a monthly bill:

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£2,100 * 16 m² / 35 m² gives £960.00

£2,100/month * 16 m² / 35 m² gives £960.00/month

A few less common operations are allowed too. Multiplying money by money works, and so do powers up to 3, but roots don’t:

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£2^3 gives £8.00

sqrt(£4) gives Error: unsupported multiplicative unit

Adding amounts in two different currencies, such as $5 + €3, needs an exchange rate. See the next section.

Converting between currencies

Convert with in, to or as, the same way you convert units. Because these answers depend on the latest exchange rates, the results below are only examples:

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€45 in GBP gives £38.58

$120 to GBP gives £89.18

£1,200 as EUR gives €1,399.58

CHF 80 in EUR gives €84.67

You can also add amounts in different currencies directly. The answer is shown in the currency of the last amount, and you can add in … to pick another:

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£50 + €20 gives €78.32

€20 + £50 gives £67.15

£50 + €20 in GBP gives £67.15

Where the rates come from

Rates for the major currencies come from the European Central Bank’s daily reference rates. The ECB publishes these once each working day, so they’re a fair guide to what a currency is worth but not a live market price, and over a weekend you’ll see Friday’s rates. Currencies the ECB doesn’t cover, and cryptocurrencies, use supplementary quotes from Coinbase. When both sources list a currency, the ECB rate is used.

If no rate is available for a currency, the line shows an error naming it, such as Error: missing rate: EUR, rather than guessing. Converting a currency to itself always works.

Using your own rate

When you want a conversion to match your bank statement or a rate you’ve agreed, add at and the rate after the conversion. The rate is how much one unit of the first currency is worth in the second. Your rate is used even when live rates are available, so these answers never change:

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€250 in GBP at 0.86 gives £215.00

$100 to EUR at 0.92 gives €92.00

Write the rate as a number. A name defined on an earlier line can’t be used in its place.

Historical rates

To convert at the rate from a particular day, add on and a date. Historical conversions use the ECB’s published history, which goes back to 1999:

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€100 to USD on 2 January 2020 gives $111.93

100 EUR to USD on January 2 2020 gives $111.93

€100 in GBP on 2 January 2024 gives £86.65

The ECB publishes rates only on its working days, so a weekend or a holiday such as 1 May has no rate. Varlig shows an error for those dates rather than borrowing a neighbouring day’s rate. Historical rates cover the currencies in the ECB’s history, not cryptocurrencies.

Cryptocurrencies

Around 150 cryptocurrencies listed on Coinbase are recognised by code or name, including BTC or bitcoin, ETH or ethereum, SOL or solana, ADA or cardano, DOGE or dogecoin, XRP or ripple, DOT, AVAX, LINK, LTC, USDC and USDT. The subunits satoshis (also sats and sat), gwei and wei convert to their coins without an exchange rate:

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0.5 bitcoin gives ₿0.5

2 solana gives 2 SOL

100000 sats in BTC gives ₿0.001

1 ETH in gwei gives 1G GWEI

1 ETH in wei gives 1e18 WEI

0.25 ETH * 4 gives 1 ETH

Converting a coin to a traditional currency uses a market quote, so the result changes over time:

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1 ETH to USD gives $2,390.88

Recognising a code doesn’t guarantee there’s a quote for it. If there isn’t, you’ll see a missing-rate error.

Prices per unit

A price per kilogram, per litre or per hour is a rate, and it behaves like any other rate. Write it with / or per, multiply it by a quantity to get a cost, and convert it to a different unit with in:

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£3.60 / 1.5 kg gives £2.40/kg

£3.50 / 500 g in £/kg gives £7.00/kg

$4/gal in $/L gives $1.06/L

£1.50/L * 40 L gives £60.00

£35/hour * 7.5 hours gives £262.50

2h 15m * £40/hour gives £90.00

£450/workday * 4 weeks gives £9,000.00

£2,400/month in £/year gives £28,800.00/year

A price per period can also be written the way you’d say it, as in £25 a month, £45k per annum or £250 weekly. See Rates for all the forms.

A rate per workday counts five workdays a week, so a £3.20 coffee on each working day comes to the same yearly figure whichever way you ask:

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£3.20/workday in £/year gives £834.84/year

£3.20/workday * 1 year gives £834.84

Dividing money by a price per unit tells you how much you can buy:

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£60 / (£1.50/L) gives 40 L

Comparing shelf prices

Shops label prices per kilogram, per 100 g or per pound. Convert a price to the amount you want to compare, written with / or per:

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£8/kg in £/100g gives £0.80/100 g

£3.50 / 500 g in £ per 100g gives £0.70/100 g

£8/kg in £ per lb gives £3.63/lb

Prices per area and length

A price per square metre times the length and width of a floor gives the cost. Multiply by the width alone and you get a price per metre, which is how carpet and vinyl cut from a 4 m roll are often sold:

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£12/m² * 4 m * 3 m gives £144.00

£22/m² * 4 m gives £88.00/m

£15/m / 3 m gives £5.00/m²

The last line goes the other way: fabric at £15 a metre from a 3 m wide roll works out at £5.00 a square metre.

Durations such as workday, week and month are covered in Clock times and durations, and rates in general in Rates, speed, pace, fuel and transfer time.

Putting it together

Here’s a note for a long weekend in Normandy, split between three friends. The cottage and meals were paid in euros, converted at the rate on the bank statement, and the fuel cost comes from the car’s consumption:

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# Long weekend in Normandy, split three ways

ferry = £186

cottage = €540 in GBP at 0.86 gives £464.40

meals = €300 in GBP at 0.86 gives £258.00

fuel = 6 L/100km * 480 km * £1.50/L gives £43.20

total = ferry + cottage + meals + fuel gives £951.60

total / 3 gives £317.20

Because each cost has a name, the total reads like the sentence you’d say out loud. Every amount is in pounds by the time it reaches total, so the answer doesn’t depend on the day’s exchange rates. Names defined here also carry into later calc blocks in the same note, so you could settle up further down the page.