Decimalisation is the process of transitioning from a fractional system of measurement into one that the financial world, decimalisation can be applied to currencies and security pricing, with fractions being replaced by subunits of 100. The dollar currency denomination and penny-increment stock pricing are examples of decimalized systems of measurement within the world of finance.

A decimal format is generally widely preferred to fractions, and so decimalisation is when the decimalised units are used for security pricing as well as for currencies.