The flag of São Tomé and Príncipe features a horizontal tricolor design with three equal stripes: green (top), yellow (middle), and green (bottom). A red triangle is placed at the hoist, and two black stars are located on the yellow stripe.

Color codes:

• Green: Pantone 347, HEX #3EB489, RGB(62,180,137), CMYK(66,0,24,29)
• Yellow: Pantone 123, HEX #FCD116, RGB(252,209,22), CMYK(0,17,91,1)
• Red: Pantone 485, HEX #DA291C, RGB(218,41,28), CMYK(0,81,87,15)
• Black: HEX #000000, RGB(0,0,0), CMYK(0,0,0,100)

Aspect ratio: 1:2

Geometric properties and measurements:

• Horizontal stripes have equal height.
• The red triangle's base coincides with the hoist side and its sides extend halfway along the green and bottom green bands.
• The black stars are five-pointed and are symmetrically placed in the center of the yellow stripe, separated from each other by a distance equal to the width of one star.
• Each black star's diameter is 1/10th of the flag's width.