Score Differential

Score Differential is the numerical value attributed to a score (Adjusted Gross Score) achieved during a round of golf. It is the value of Handicap Index that has been ‘played to’ for the round on a specific course on a specific day.

It is calculated with a simple formula and expressed as number rounded to one decimal place. The consecutive Differentials are chronologically registered in the scoring record of a player. They are the basis for calculation of the player’s Handicap Index.

score differential in WHS

The adjustment of a Handicap Index relies on 18-hole Score Differentials. Therefore 9-hole scores have to be converted into their 18-hole equivalents. Two methods are used for this (in EGA countries both options are used):

  • a 9-hole score is scaled up to an equivalent 18-hole Score Differential (an option for Great Britain, Ireland and South Africa), or
  • a 9-hole score is combined with another 9-hole round Score Differential to create an 18-hole value (an option for US, Australia and Argentina).

The calculator below calculates:

  • 18-hole Score Differential for 18-hole round, or
  • 9-hole Score Differential (for combining with another 9-hole score) and its 18-hole equivalent (for immediate use) for 9-hole round.


The Score Differential is registered in the scoring record of this player as the score of the round for handicap purposes (Handicap Index calculation).

back to: Handicap

update: April 2021