De Kalb spans nearly 50,000 acres, with the Oswegatchie River flowing through the center of town. Harrison's Creek flows through the southeastern corner and Beaver Creek flows between De Peyster and De Kalb. Mining these fertile rivers and several other of De Kalb's small streams has produced pyrites, barytes and limestone.

The economy of St. Lawrence County has historically depended on the St. Lawrence and Oswegatchie rivers and numerous resources common in the region. Area industries have included lumbering, paper production, foundry work, machine work, boat building and a variety of milling work. The arrival of a railroad and the establishment of a junction with a line to Ogdensburg had a permanently positive effect on De Kalb's future economic interests. Until that time, early settlers in De Kalb relied primarily on potash made while clearing their farms and lumber; this was sent down the river to nearby Ogdensburg. As De Kalb's landscape was cleared out, the area's agricultural interest rapidly began to develop. In recent years, dairy products, such as butter and cheese have become a thriving industry. One of the original cheese factories is now a butter creamery with a thriving market in Boston. With several flourishing factories in operation, cheese remains the primary product, and De Kalb ranks third in the nation in the quantity of cheese manufactured.

De Kalb is known as St. Lawrence County's "antique capital" due to its numerous antique shops, flea markets and auctions. Many of the area's country roads have vegetable stands, and farmer's markets are sprinkled throughout the countryside. De Kalb has a variety of interesting historic sites such as the Old Methodist Meeting House, and a number of developed parks for recreation. It is De Kalb's centralized location within the Ogdensburg-Massena metro area that affords residents a multitude of entertainment and career options. Massena serves as the hub of commerce and industry for St. Lawrence County and is home to the St. Lawrence Centre Mal. It is also home to major employers such as Alcoa. Ogdensburg lies within the gorgeous Thousand Islands region, which offers an family-friendly activities and is home to the Port of Ogdensburg. Via this port, area businesses have easy access to major markets throughout the state as well as in Boston, Philadelphia, Canada and Northern Europe.

In addition to its central location, thriving economy, and below average violent crime rate, residents have access to twenty-two modern schools located throughout the Greater Ogdensburg Area. A number of quality higher learning institutes can be found within a reasonable distance of De Kalb. This includes St. Lawrence University in Canton, SUNY Canton, SUNY Potsdam, Clarkson University in Potsdam and the New York State Ranger School in Wanakena.