SI - The Metric System for Travelers - (2) - Conversion and Equivalents

A Primer for
Travelers to Europe

Using Metrics

Complete Listing of Ed and Julie's
Travel Tips and Planning Tools

Continued from Page 1 - Quick Reference Formulae

owever useful a second language may be, it's usually helpful in only a handful of countries. Knowing metric prepares you to travel almost anywhere.

Only the United States, Liberia and Burma are not committed to its use as the measurement system of everyday life. Why worry about looking like a tourist if you can't even size things up like the natives?

Not understanding distances and weights and temperatures may leave the impression you're ill-educated. The system is easy to learn. Go to Europe armed with at least a minimum understanding.

measurements are 'foreign' to many Americans. However, they're simple to use and accustom oneself to. It just takes some time. You might even find they make more sense than the measures we're used to.

The SI was developed in the late 18th Century to facilitate trade and travel. Become a more worldly person when you're traveling abroad. Take the time, after 200 years, to get familiar with the standard world language of measurement.

Note that everything on this website is written using US numeric notation. In Europe commas and periods are reversed for number group separators and decimal place indicators. Thus, in the US we'd write 1,001.5 for one thousand one and a half, while in Europe it would be written 1.001,5. If you're interested we have more on writing numbers and dates, European style.

Distance

here we use miles, Europeans use kilometers (km), or a distance equal to 1,000 meters. A kilometer is about 5/8 of a mile, or, precisely, 0.62137 mile. Conversion from kilometers to miles is pretty easy -- just multiply by six and divide by ten (drop the last digit). If you're worried about precision, you can add 2% to the result and you'll be within a decimal place of the correct answer.

Where, on US highways, you would find a sign saying "Next Exit 1 Mile" you'll find one saying 1 kilometer or, more commonly, "1000 m". Since this is less than 2/3 the distance you're used to in the US, be prepared for the exit to show up sooner. Often you'll find a subsequent sign saying "500 m". You'd better be in the right-hand lane by then if you're on an Autobahn traveling at 150 km/h since the exit will show up in 12 seconds!

he meter is the common measure used where we would use feet (or yards). If you're told the Post Office is about 100 meters down the street you can think of that in yards since one meter equals about 1.1 yards, or 3.3 feet. (Multiply meters by 3 and add 10% for feet; just add 10% for yards.)

You'll be pretty close if you think of a meter or a yard as being about the same as the distance from your nose to your outstretched fingertips or a very long pace.

Height

eters for mountains, centimeters for people.

How high is that mountain? Measured in meters in Europe, just like the distance to the Post Office. A 3,100 meter mountain in Europe would be 10,000 feet high in the US.

Most adult travelers are between 150 and 190 centimeters tall. Julie is 159 cm and Ed about 182, or 1.59 and 1.82 meters. What's your metric height?

Speed

ot surprisingly, kilometers per hour (km/h) is the basic measure. As in distance, 100 km/h = 62.137 mph. Estimate your speed by multiplying by 6, dividing by ten, and adding about 2% if you're fussy about the result. (Important note: the UK still uses miles and miles per hour.)

enerally, by the way, countries have consistent nationwide speed limits for built-up areas, areas between towns, and for their superhighways (e.g. Autobahns.) You'll find neither the plethora of state-to-state variations found in the US nor the bewildering variety of limits often found throughout a single city. Since there are usually only three limits to worry about, they'll often not be posted -- you are expected to know what they and where they apply. A little study ahead of time may keep you out of hot water.

Whatever you do, do not confuse speed limit signs in km/h with an mph limit -- you'll find yourself in the clink for ignorance ... or for killing that cow.

Length

eters are used in place of feet or yards. A meter (m) contains 39.3701 inches, 3.28084 feet, or 1.0936 yards. To roughly convert meters to feet multiply by 3 and add 10%; to get yards, add 10% to meters.

or shorter distances centimeter (cm) substitutes for inch. The thickness of an 'average' index finger at the base of the nail is roughly a centimeter, or about 3/8 inch. The legal definition of an inch is 2.54 cm. Multiplying centimeters by 2.5 will get you close to the inch equivalent (or divide by 0.4 if you prefer.) Or, think of 4 inches as 10 centimeters ... close enough if you're not using a micrometer

Area

he traveler will find the size of archaeological sites, farms or parks, for example, described as so many hectares. A hectare contains 2.471 acres. (An "are" is 100 square meters ... a hectare is 10,000 square meters ... 100X100.)

You'll be close if you multiply hectares by 2.5 to get acres. If you're describing your farm to a European, divide your acreage by 2.5 ( or multiply by 0.4) to convert to hectares.

Descriptions of large areas (e.g. countries or forests) may include the size in square kilometers. A km² is 0.3861 mi². Multiply by 0.4 (or divide by 2.5) to approximate the area in square miles.

quare inches, feet and yards are replaced by square centimeters and meters. A square centimeter is mighty small, about 0.155 square inches; divide by 6 to get a rough square inch equivalent. A square meter is 10.7639 square feet.

If you want to tell a European how large your apartment is (which you think of in square feet), divide by 11 and you'll be pretty close to the equivalent in square meters. You can 'translate' her apartment's size by multiplying her square meters by 11 to get square feet.

Volume

liter (L) is just a little over 5% more than a quart. A milliliter (mL) is equivalent to a cubic centimeter (cc). A liter is 1,000 cubic centimeters. (Fortunately it's not called a kiloliter ... which is what our grandchildren usually do with a bottle of cola during a visit.)

It's usually appropriate to consider a liter and a quart as being equivalent; It's difficult to order 943.3 milliliters (= a quart) of milk. A half liter is equivalent to a pint. A measuring cup is almost 250 mL.

here is no direct unit equivalent for gallons. Four liters is close to a gallon.

ottled water, soda and most other liquids are sold. universally, by the liter or two-liter bottle, as is now common in the US.

In a restaurant, though, where you are dictates your choices of how much you get when you order a beverage. In (French-speaking) Switzerland, for example, wine is sold at table in 2-deci (2-deciliters = 1/5 of a liter), 3-deci, and 5-deci glasses or decanters as well as by the liter or bottle. A 2-deci serving is adequate for one person; 3-deci is generous; 5-deci will serve two nicely. (In German-speaking Switzerland these become 2-dezi, etc.) In Italy you may find only a choice between a 1/2 liter or full liter reflecting the wine-drinking nature of the country.

In Germany you order wine by the glass (usually somewhere around 2 or 3 deciliters), or 1/4, 1/2, or whole liter, or by the 'bottle'. "Standard" sizes often differ within country by region. In most of Germany an order for, "Ein Bier, bitte", will produce a half liter of beer unless you order the extra large size. In Bavaria, though, unless you order a small beer you'll get a liter as the standard.

ne liter = 1.0567 quart or 0.26417 gallon -- Estimate 1:1 for quarts or 1:4 for gallons and add a smidgen (~5%.)

Weight

ilogram (kg) replaces pounds. A kilogram contains 2.20462 pounds. Multiply by 2 and add 10% and you'll have the weight in pounds. A gram is 1,000th of a kg.

Where you might buy a quarter pound of bologna in a deli for two sandwiches, a European would probably order 100 grams (for slightly smaller sandwiches ... about 13%, to help your diet.) (In Italy they'd order an 'etto', 1 hectogram, the same 100g.)

arger containers will be marked in kg or fractions (e.g. 0.500 kg or 500 g, a bit more than a pound, which is 454 g.) Small quantities are usually packaged or served in 'round' gram amounts: 15 grams, about 1/2 ounce or almost 1 tablespoon of butter; 25, 30 or 50 grams of jelly or caviar, about one or two ounces.

Gas Mileage

or whatever historical reasons, Americans think of fuel consumption in terms of miles per gallon. Europeans measure it in the equivalent of gallons per hundred miles, or, actually, liters per 100 kilometers.

The two measurements are somewhat like apples and pears: they're similar, but different. Fortunately, there is a way to get from here to there.

The precise formula from European liters per 100 km to mpg is 62.127/(liters*0.26417) Example: 12 liters per 100 km = 62.127/(12*0.26417) = 19.6 mpg.

For a simpler approximation multiply the liters number by 0.4 and divide 100 by the result. Using the same 12 liters per 100 km, 12*0.4=4.8 and 100/4.8 = 20.8 mpg. The approximation is high by about 6%, but close enough to know whether you're renting a gas guzzler or an economy model. Stick with small-engine cars and manual transmissions and you won't have to worry about the price of petrol.

Temperature

he Fahrenheit scale is used mainly in the United States. It's useful mainly because Americans get used to it: water freezes at +32^oF and boils at +212^oF.

The Celsius scale is used throughout the world. In the US we used to call it the Centigrade scale when some of us went to school. Since we caught on to it, they changed its name. The basis for the scale is the freezing/boiling range of water: 0^oC at freezing, and 100^oC at boiling. (This is where the "Centigrade" part came from -- a 100-point scale.) This system is used by most of the world, including most scientists. The Celsius scale normally accompanies the SI though it's not, technically ,a part of it.

hen the forecast is for 15degrees Celsius (15 ^oC) up in the Swiss Alps, how cool is that to Americans? About 59^oF. The basic formula is ^oF = 9/5(^oC)+32. (Multiply the Celsius number by 9, then divide by 5 and add 32 to the result.)

Useful if you're running the numbers on the computer, but a hassle if you're in the mountains. You can get close by doubling the Celsius temperature, taking away 10% and adding 32. (e.g. 15 times 2 = 30, take away 3 leaves 27, and add 32 to get 59 ... in this example it's right on the money.)

If that's still a little complicated, for common mild temperatures you can get away with doubling the Celsius temperature and adding 30. (15X2+30 = 60) -- a little off, but close enough to know what to wear. Try it on the current temperature shown for Bern above and see how close this comes.

ven simpler, if very rough: 0^oC is freezing, 10^oC is quite chilly, 20^oC is coolly comfortable, 30^oC is quite warm, and 40^oC is desert heat.
(US 'room temperature' (72^oF) is about 22-23^oC ... you'll find it closer to 20 ^oC in Europe, though.)

Back to our Quick Reference table of commonly used metrics. Or perhaps you'd like it in a small size to print it to take with you on your trip? Or, use our online metric conversion spreadsheet.

References

In-depth Information on the Modern Metric System
U.S. Metric Association A wealth of information and services related to U.S. metrication.
SI Navigator: A comprehensive collection of links to the best sites for metric information.
More on the Metric System.

Would you like to be able to convert all units easily at your computer? Flow Simulation International has a fine freeware replacement for your Windows calculator that does the job handily.

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