The flag of South Africa has a width-to-length ratio of 2:3, and consists of six equal horizontal bands of black, yellow, green, white, gold, and red from top to bottom. The central design is a "Y"-shaped pattern in green, with arms curving outward and upward, at the fly-end of the hoist-side half of the flag. The vertical band on the hoist side contains the flag's colors and the centrally-placed coat of arms of South Africa. The colors are defined using the Pantone Matching System as:

• Black: Pantone Process Black C
• Yellow: Pantone 116 C
• Green: Pantone 355 C
• White: unprinted (white)
• Gold: Pantone 1235 C
• Red: Pantone 186 C.

There are no official measurements or geometric properties specified for the flag, but the proportions of the emblem match those of the flag itself.