Bali lies 3.2 km east of Java and about 8 degrees south of the equator. It is 153 km long and 112 km wide (95 by 69 miles). Its surface area is 5,633 km². The highest point is Mount Agung, 3,142 m high (10,308 feet), an active volcano that last erupted in March 1963. Mountains range from the central to the eastern side, Mount Agung being the easternmost peak. Mount Batur, or what remains of it, is also still active. About 30,000 years ago it experienced a massive catastrophic eruption — one of the largest known volcanic events on Earth.

The principal cities are the northern port of Singaraja and the capital, Denpasar, near the southern coast. The town of Ubud (north of Denpasar), with its art market, museums and galleries, is regarded as the cultural center of Bali.

In the south the land descends to form an alluvial plain, watered by shallow rivers, dry in the dry season and overflowing during periods of heavy rains.

Its population of over 3 million is mainly (about 93%) Hindu, but a very small part is Muslim (mostly coastal fishermen).

The main tourist locations are the town of Kuta (along with its accompanying beach), Sanur, Jimbaran, Seminyak and the newer development of Nusa Dua. The Ngurah Rai International Airport is located near Jimbaran, on the isthmus joining the southernmost part of the island to the main part of the island.

There are major coastal roads and roads that cross the island mainly north-south. Due to the mountainous terrain in the island's center, the roads tend to follow the crests of the ridges across the mountains. There are no railway lines.

The island is surrounded by coral reefs. Beaches in the south tend to have white sand while those in the north and west black sand. The beach town of Padangbai in the north east has both: the main beach and the secret beach have white sand and the south beach and the blue lagoon have much darker sand.

Pasut Beach (Tabanan), near Sungai Ho and Pura Segara, is a quiet beach 14 km southwest of Tabanan. The Ho River is navigable by small sampan. Facing a revitalizing landscape of strong waves, the coast around Pasut is a perfect escape from the crowds. Beautiful black sand beaches between Pasut and Klatingdukuh are now being developed for tourism, but apart from the famous seaside temple of Tanah Lot, this is not yet a tourist area.

Most of the Balinese people are involved in agriculture, primarily rice cultivation. Crops grown in smaller amounts include fruits, vegetables and other cash crops. A significant number of Balinese are also fishermen. Bali is also famous for its artisans who produce batik and ikat cloth and clothing, wooden carvings, stone carvings and silverware.