Calamba covers an area of 14,480 hectares, which are about 8.22% of the province's total land area. The municipality is comprised of 54 barangays: Barangays 1-7, Bagong Kalsada, Banlic, Banadero, Barandal, Batino, Bubuyan, Bucal, Bunggo, Burol, Camaligan, Canlubang, Halang, Hornalan, Kay-Anlog, Laguerta, Lamesa, Lawa, Lecheria, Lingga, Looc, Mabato, Majada-Labas, Makiling, Mapagong, Masile, Maunong, Mayapa, Paciano Rizal, Palingon, Palo-Alto, Pansol, Parian, Prinza, Punta, Puring-Lupa, Real, Saimsim, Sampiruhan, San Cristobal, San Jose, San Juan, Sirang-Lupa, Sucol, Tulo, Turbina, Ulango, and Uwisan. Among the barangays, Canlubang, which is located on the western part of the municipality, is the largest in terms of population, income and area.

The terrain of Calamba is generally rugged. The relief ranges from level to hilly and mountainous. The major portion of the eastern, southern and western parts of the town is a belt of hills and mountains .

The slope of the different barangays in the municipality ranges from level to steeply sloping.

Clastic rocks is dominant in the areas of San Cristobal, Mapagong, Lawa, Batino, Mayapa, Prinza, Barandal, Tulo, Palo-Alto, Punta, Makiling, Ulango, Kay-Anlog, Bubuyan, Laguerta, Burol, Hornalan, Bunggo, Sirang-Lupa, Majada-Labas, Canlubang, and Mabato.

Alluvium is commonly present in the poblacion areas and nearby barangays.

The basis of climate classification is the type of rainfall. Calamba falls under the forest type of rainfall. There are two pronounced seasons: dry from December to June and wet from June to December. Heavy rains usually fall on June, July, August and September. Dry season is more pronounced in the northwestern part of the municipality.

The temperature does not show much variation from year to year. It is generally warm in April to June and cool from December to February. The highest and lowest temperatures were 29.5 °C in April 1990 and 25.7° C in January.

The relative humidity (RH) during 1986-1990 has an average of 79.3% at a range of 78.88%. Relative humidity and seasonal variations in temperature are similar in Manila, though the temperature especially in the elevated areas is generally lower than the temperature in Manila. The coldest months are on October, December and January.

There are three (3) prevailing wind directions throughout the year:

• the east wind occurs during January to June 
• the northeast wind occurs during October to December 
• the west and southwest winds occur from July to September