Note · Service

Seven tools for Europeans visiting the US

After moving to San Francisco I found myself constantly converting basic units and figures. After a while I got tired of using a different formula or service every time – so I built my own forms. Here you can quickly convert lengths, times, temperatures or fuel economy. The exchange-rate tool covers the euro–dollar pair; for British pounds or Swiss francs the same approach applies – see the source link.

AI-generated illustration of digital tools
AI-generated illustration

A few notes upfront: differences in date, address and phone formats

The United States and most European countries use different conventions for writing dates, postal addresses and phone numbers. A few examples:

Date format

In the US the date is written month/day/year; most of Europe uses day.month.year (or day/month/year in the UK). This can lead to confusion when both day and month are below 13.

USA
MM/DD/YYYY – e.g. 06/25/2023
Continental Europe
DD.MM.YYYY – e.g. 25.06.2023
UK
DD/MM/YYYY – e.g. 25/06/2023

Postal address

Order differs. In the US the state is given as a two-letter abbreviation; the ZIP code follows directly after the city.

USA
John Smith
123 Main Street, Apt 4B
New York, NY 10001
Germany
Max Mustermann
Musterstraße 123
12345 Musterstadt
UK
Jane Smith
123 High Street
London SW1A 1AA

Phone numbers

For international exchanges, the country code (+1 for the US, +49 for Germany, +44 for the UK) is given; the leading zero of the local prefix then drops away.

USA
(###) ###-#### – e.g. (123) 456-7890
Germany
+49 (0) ####-#### – e.g. +49 1234 567890
UK
+44 (0) #### ###### – e.g. +44 20 7946 0000
01

Exchange rate: EUR to USD – 12 months

The euro–dollar exchange rate moves around a lot. The chart shows the path of the past twelve months, based on the official ECB reference rates (data source: frankfurter.app). For the exact daily rate, see the European Central Bank's form.

02

Convert euros to US dollars

Convert single values directly. By default the form uses today's date; historical rates are also available.

03

Length conversion

Inches, yards and miles to centimetres, metres and kilometres – or back.

ImperialFactorMetric
1 inch = 2.54 cm
1 yard = 0.9144 m
1 mile = 1.60934 km
04

Area conversion

From square inches to square miles in their metric equivalents.

ImperialFactorMetric
1 sq in = 6.4516 cm²
1 sq ft = 0.092903 m²
1 sq yd = 0.836127 m²
1 acre = 0.404686 ha
1 sq mi = 2.58999 km²
05

Temperature conversion

Fahrenheit to Celsius: subtract 32, then multiply by 5/9. Celsius to Fahrenheit: multiply by 9/5, then add 32. Or just use this:

FahrenheitCelsius
06

Time: US West Coast ↔ Central Europe

Converts between US West Coast time (PST) and Central European Time (CET). Note: daylight-saving switches don't happen on the same day in the US and Europe. For roughly two weeks in March and one week in October/November the time difference is only eight rather than nine hours. UK time (GMT/BST) is one hour earlier than CET.

US West Coast (PST)Central Europe (CET)
07

Fuel economy: MPG ↔ l/100km

In the US, fuel economy is measured in miles per US gallon (MPG) – higher number = more efficient. Most of Europe uses litres per 100 km – lower number = more efficient. The conversion: 235.215 divided by one value gives the other. Note: the UK still uses miles per Imperial gallon for older formats, which is a slightly different unit.

Miles per US gallonLitres per 100 km