- Area: 3,103,200 km².
- internal: Chukotka (E), Magadan Oblast (E/SE), Khabarovsk Krai (SE), Amur Oblast (S), Chita Oblast (S), Irkutsk Oblast (S/SW), Evenkia (W), Taymyria (W/NW).
- water: Arctic Ocean (including Laptev Sea and Eastern Siberian Sea) (N).
- Highest point: Peak Pobeda (3,003 m) or Peak Mus-Khaya (3,011 m).
- Maximum N->S distance: 2,500 km.
- Maximum E->W distance: 2,000 km.
- Average elevation: no data.
Sakha stretches to the Henrietta Islands in the far north and is washed by the Laptev and Eastern Siberian Seas of the Arctic Ocean. These waters, the coldest and iciest of all seas in the northern hemisphere, are covered by ice for 9-10 months of the year. New Siberian Islands are a part of the republic's territory.
Sakha can be divided into three great vegetation belts. About 40% of Sakha lies above the Arctic circle and all of it is covered by permafrost which greatly influences the region's ecology and limits forests in the southern region. Arctic and subarctic tundra define the middle region, where lichen and moss grow as great green carpets and are favorite pastures for reindeer. In the southern part of the tundra belt, scattered stands of dwarf Siberian pine and larch grow along the rivers. Below the tundra is the vast taiga forest region. Larch trees dominate in the north and, in the south, stands of fir and pine begin to appear. Taiga forests cover about 47% of Sakha and almost 90% of this cover is larch.
Sakha spans three different time zones:
- Yakutsk Time Zone (YAKT). UTC offset is +1000 (YAKT). Covers the republic's territory to the west of the Lena River as well as the territories of uluses located on the both sides of the Lena River.
- Vladivostok Time Zone (VLAT). UTC offset is +1100 (VLAT). Covers most of the republic's territory located between 127°E and 140°E longitude.
- Magadan Time Zone (MAGT). UTC offset is +1200 (MAGT). Covers most of the republic's territory located east of 140°E longitude.
Navigable Lena River (4,310 km), as it moves northward, includes hundreds of small tributaries located in the Verkhoyansk Range. Other major rivers include:
- Vilyuy River (2,650 km)
- Olenyok River (2,292 km)
- Aldan River (2,273 km)
- Kolyma River (2,129 km)
- Indigirka River (1,726 km)
- Olyokma River (1,320 km)
- Yana River (872 km)
- Alazeya River
- Amga River
- Anabar River
- Markha River
- Maya River
- Muna River
- Nyuya River
- Sedennyakh River
- Tyung River
There are over 700 lakes in the republic. Major lakes and reservoirs include:
- Mogotoyevo Lake
- Nedzheli Lake
- Nerpichye Lake
- Vilyuyskoye Reservoir
Sakha's greatest mountain range, the Verkhoyansk Range, runs parallel and east of the Lena River, forming a great arc that begins the Sea of Okhotsk and ends in the Laptev Sea.
The Cherky Range runs east of the Verkhoyansk Range and has the highest peak in Sakha, Peak Pobeda (3,003 m). Recent satellite photos, however, revealed that Peak Mus-Khaya may in fact be a higher point, reaching 3,011 m.
Further east lie the gold-rich Kolyma Mountains, which stretch all the way to Chukotka.
The Stanovoi Range borders Sakha in the south.
Sakha is well endowed with raw materials. The soil contains large reserves of oil, gas, coal, diamonds, gold, and silver. 99% of all Russian diamonds are mined in Sakha, accounting for over 13% of the world's diamond production.
Sakha is known for its climate extremes, with the Verkhoyansk Range being the coldest area in the northern hemisphere. The Northern Hemisphere's Pole of Cold is at Oymyakon, where the temperatures reached as low as −72.2°C in January of 1926.
- Average January temperature: −28°C (coast) to −50°C (other territories).
- Average July temperature: +2°C (coast) to +19°C (central parts).
- Average annual precipitation: 200 mm (central parts) to 700 mm (mountains of Eastern Sakha).