225.49% is the change from 255 to 830
Calculation steps:
[( 830 - 255 ) ÷ 255] x 100 = 225.49%
Formula
Percentage change = [(830 - 255) / 255] x 100
Subtract the new number by the original number
830 - 255 = 575
575 ÷ 255 = 2.2549019607843137
2.2549019607843137 x 100 = 225.49%