In Brazil, the dot is used to separate thousands and the coma is used to express decimals. For example:

• 1,000 in Brazil is “one”.
• 1,000 in the USA is “a thousand”.
• 1.234 in Brazil is “a thousand, two hundred and thirty-four”.
• 1.234 in the USA is “one point two hundred thirty-four” that is, less than one and a quarter.  

If the date is indicated in the numerical way, in Brazil it is written in the day/month/year format. Example:

• In Brazil, 12 / 5 / 2008 is May 12, 2008. Nos EUA, 12 / 5 / 2008.
• In the USA, 12 / 5 / 2008 is December 12, 2008.

Tip: always write or abbreviate the name of the month with letters instead of numbers:

• 5 / Nov / 2007 and Nov / 5 / 2007 mean the same in Brazil and in the USA.
•  Abbreviation of months in Portuguese: Jan, Fev, Mar, Abr, Maio, Jun, Jul, Ago, Set, Out, Nov, Dez.

• Areas are indicated in square kilometer (km²).  
• 1 square kilometer = 0,39 square mile.
• 2,59 square kilometers = 1 square mile.
• 1 kilometer = 0,62 mile
• 1 mile = 1,61 kilometers

• In Brazil, real estate property areas are expressed in square meter (m²).  
• 1 square meter = 10,7 square foot
• 1 square meter = 0,000 24 acre

• 1 cm² = 0,1550 square inches.
• 1 m² = 1,196 square yards.

• Weight in general is indicated by kilos (kgs).  
• 1 kilogram = 2,204 pounds.
• 1 pound (lb) = 453 grams.
• 1 libra (pound) = 0,45359237 kg
• The weight of small things is measured in grams. And 1000 grams=1 kilo.
• In Brazil, 1 ton = 1000 kilos.

• Length in Brazil is measured in meters (m) and centimeters (cm), where 1 meter= 100 centimeters.
• 1 meter = 3,28 feet.
• 1 meter 39,37 inches.
• 1 foot = 30,48cms.
• 1 inch = 2,54 cms.
• 1 centimeter = 0,3937 inches.
• 1 meter = 1,0936 yards.
• 1 yard= 36 inches = 0,9144 meters = 91,44 cms.
• The height of people is expressed in meters and centimeters: 1.75 = 1 meter and 75 centimeters = 5’9” (5 feet and 9 inches).

• The volume of liquids is measured in liters (L) and mililiters (ML) in Brazil. 1 L = 1000 ML.
• 1 liter = 33,814 ounce [US, liquid]
• 1 liter = 0,264 gallon [US, liquid]
• 1 gallon = 3,785 liter
• 1 ounce = 29, 573 milliliters (ML).

• The distance is measured in kilometers.  
• 1 kilometer = 0,621 miles.
• 1 mile = 5.280 feet = 1,609 km = 1.609 meters.
• 1 nautical mile = 6.076 feet = 1,852 km = 1.852 meters.

The speed in transportation vehicles is expressed in kilometers per hour (km/h).

• The temperature in Brazil is measured in Celsius degrees (ºC).
• 212 ºF = 100 ºC e 32 ºF = 0 ºC.
• Weather in Brazil: www.weather.com

For very specific itens: http://n93.cs.fiu.edu/measures

Another excelent website is www.convert-me.com/en.