Abstract: The invention relates to a folding board for folding paper (A) of a standard size, such as stationary, to which end the folding board is provided with position checks (2,3) for holding the paper to be folded in position as well as with a folding mark (4). Thanks to the folding mark (4) it is possible to quickly and accurately fold paper in three. Further folding marks make the folding board suitable for different standard paper sizes, such as DIN A4 and US letter paper. Using the aid, paper can also quickly, easily and accurately be folded double or folded twice double.