In Highcharts, there is an array containing the default colors for the chart's series. When all colors are used, new colors are pulled from the start again.
Defaults colors for version 4.x and 5.x are:
colors: [
'#7cb5ec',
'#434348',
'#90ed7d',
'#f7a35c',
'#8085e9',
'#f15c80',
'#e4d354',
'#2b908f',
'#f45b5b',
'#91e8e1'
]
In Highcharts 3.x, the default colors were:
colors: [
'#2f7ed8',
'#0d233a',
'#8bbc21',
'#910000',
'#1aadce',
'#492970',
'#f28f43',
'#77a1e5',
'#c42525',
'#a6c96a'
]
In Highcharts 2.x, the default colors were:
colors: [
'#4572A7',
'#AA4643',
'#89A54E',
'#80699B',
'#3D96AE',
'#DB843D',
'#92A8CD',
'#A47D7C',
'#B5CA92'
]