
It's about as big as a Bathtub.
(a.k.a. bath, a.k.a. tub) (for Bootz Industries Aloha 5 ft. Left Hand Drain Soaking Tub)
The capacity of a typical bathtub is 680 cups. Historically, bathtubs have been made of various materials including marble, terracotta, silver, gold, and iron but the size and shape of the tubs has changed little in their 7,000 year history.
It's about two times as big as a Car Gas Tank.
In other words, 680 cups is 2.130 times the size of a Car Gas Tank, and the size of a Car Gas Tank is 0.4690 times that amount.
(for 2009 Ford Taurus)A car gas tank (for example, that of a 2009 Ford Taurus) holds 320 cups of gas. In contrast, the Curved Dash Oldsmobile — the first massproduced car — had a fuel capacity of just 84.50 cups.
It's about twoandahalf times as big as a Beer Keg.
In other words, 680 cups is 2.740 times the size of a Beer Keg, and the size of a Beer Keg is 0.3650 times that amount.
(Half barrel; maximum capacity)The most common keg size sold by US beer sellers is a halfbarrel type with a volume of 248 cups. This type of keg contains the equivalent of 165 1.50 cups cans of beer.
It's about onefifth as big as a Hot Tub.
In other words, 680 cups is 0.2240 times the size of a Hot Tub, and the size of a Hot Tub is 4.460 times that amount.
(for Lifesmart Rock Solid Simplicity Plug and Play 4 Person Spa With 12 Jets) (a.k.a. Spa, a.k.a. Jacuzzi, a.k.a. Whirlpool) (Advertised Capacity)An average, fourperson hot tub holds 3,040 cups of water. Modern hot tubs became popular outside of Japan starting in about 1940.
It's about fourteenandahalf times as big as a Basketball (packed).
In other words, 680 cups is 14.4932516070 times the size of a Basketball (packed), and the size of a Basketball (packed) is 0.068997629181 times that amount.
(64% packing density) (NBA official ball standards, Size 7)A NBA official ball, manufactured by Spalding, is a Size 7 ball measures about 30.027768218 cups. These balls have 4,118 pebbles each with a diameter of 2.5 mm
It's about nineteenandahalf times as big as a Bowling Ball (packed).
In other words, 680 cups is 19.5400416220 times the size of a Bowling Ball (packed), and the size of a Bowling Ball (packed) is 0.05117696366 times that amount.
(64% packing density) (USBC specifications; tenpin)According to United States Bowling Congress specifications, a tenpin bowling ball should measure at least 10.795 cm (4.25 in) in radius for a total volume of about 22.2722145850 cups. Because regulation balls measure the same diameter irrespective of their weight, ball density varies by size and balls weighing less than about 5 kg (11 lbs) will float in water.
It's about twenty times as big as a Basketball.
In other words, 680 cups is 22.6457056370 times the size of a Basketball, and the size of a Basketball is 0.044158482673 times that amount.
(NBA official ball standards, Size 7)A NBA official ball, manufactured by Spalding, is a Size 7 ball and measures about 30.027768218 cups. The surface of these balls have 4,118 pebbles with a diameter of 2.5 mm each. 
