Baggage allowance varies considerably from airline to airline. Ask your travel agent for the specific rules concerning a particular flight.
Here are specifications regarding hand luggage from the airlines own homepages:
Air Baltic: Business class ticket: 2 pieces 50x40x23 cm. Other types of tickets: 1 piece. 50x40x23 cm. Maxiumum weight of one piece of hand luggage is 8 kilograms.
Atlantic Airways: 1 piece 50x40x25 cm plus 1 laptop computer, total max 8 kilograms.
British Airways: 1 piece 56x45x25 cm, max 6 kilograms.
Cimber Sterling: 1 piece 50x40x25 cm (the sum of the dimensions must not exceed 115 cm), max 8 kilograms.
DAT: 1 piece 50x40x30 cm, max 5 kilograms.
Iceland Express: 1 piece 55x35x25 cm plus laptop computer, a small handbag, and a bag with taxfree goods, the total weight must not exceed 10 kilograms.
KLM: C-class ticket: 1 piece 55x35X25 cm and 1 piece 45x35x20 cm. total max 18 kilograms. Other types of tickets: 1 piece 55x35x25 cm, max 12 kilograms.
Lufthansa: 1st class or Business Class ticket: 2 pieces 55x40x20 cm max. 8 kilograms a piece and a small handbag. Other types of tickets: 1 piece 55x40x20 cm plus a small handbag, max 8 kilograms.
Ryanair: 1 piece 55x40x20 cm, max 10 kilograms.
If you are on a transit flight to continue with an other airline, remember to check its rules!
Travellers to the American Continent are allowed to carry 2 pieces of luggage of either 23 kilograms or 32 kilograms each, depending on airlines and type of ticket. Ask the airline!
As a rule, you must pay extra if you travel with sports equipment such as a golf bag, a bicycle, a windsurf board, diving equipment. The charges vary from one airline to the other.
Be aware that the maximum weight of each piece of baggage is 32 kilograms - due to handling requirements.