Sometimes the golf ball doesn't look like it can ever fit in a golf hole. And sometimes the golf hole looks so big that you'll never miss. So, what size is the golf ball and golf hole?
The size of both are regulated in the Rules of Golf by the USGA and R&A. The golf ball has a floor minimum diameter of 1.68 inches, but it doesn't have a maximum. Golf balls are made to that spec almost universally. The golf ball also cannot weigh less than 1.62 ounces.
In the not-too-distant past, the golf ball was not a uniform minimum size everywhere. The USGA had the 1.68-inch standard, but the R&A had what was dubbed the British "small ball" with a rule that allowed players outside of the United States and Mexico (where the USGA governs) to use a ball that was 1.62 inches. The small ball was outlawed from R&A-run championships, namely the British Open, in 1974. In 1990, the R&A finally banned the small ball altogether for play, some 60 years after the USGA adopted the 1.68-inch standard.
The size of a golf hole is 4.25 inches, and it must be cut in a circular shape. That's been long done at golf courses by a standardized tool that digs into the ground to cut the 4-and-a-quarter inch hole. The compacted earth pulled from the ground using the tool is then transported to plug the previous hole so the green surface is smooth. Curiously, there is no mandatory depth of a golf hole, but it must be 4 inches deep. A cup is not mandatory either.
It is believed that the standard hole size was created at Royal Musselburgh Golf Club in Scotland in 1829 when they invented the first known hole-cutter that produced a 4.25 inch hole and was based on the typical Musselburgh drainage pipe at the time. The R&A adopted that standard width in 1891. The USGA followed suit.
In recent years, there has been movement to make golf easier by promoting a larger 8-inch hole. However, that hasn't taken wide hold in golf.