Syntax:

FormatConditions.Add(Type, Operator, Formula1, Formula2)

Parameters:

Name	Required / Optional	Data Type
Type	Required	XlFormatConditionType
Operator	Optional	Variant
Formula1	Optional	Variant
Formula2	Optional	Variant

XlFormatConditionType enumaration:

Name	Description
xlAboveAverageCondition	Above average condition
xlBlanksCondition	Blanks condition
xlCellValue	Cell value
xlColorScale	Color scale
xlDatabar	Databar
xlErrorsCondition	Errors condition
xlExpression	Expression
XlIconSet	Icon set
xlNoBlanksCondition	No blanks condition
xlNoErrorsCondition	No errors condition
xlTextString	Text string
xlTimePeriod	Time period
xlTop10	Top 10 values
xlUniqueValues	Unique values

Formatting by cell value:

With Range("A1").FormatConditions.Add(xlCellValue, xlGreater, "=100")
    With .Font
        .Bold = True
        .ColorIndex = 3
     End With
End With

Operators:

Name
xlBetween
xlEqual
xlGreater
xlGreaterEqual
xlLess
xlLessEqual
xlNotBetween
xlNotEqual

If Type is xlExpression, the Operator argument is ignored.

Formatting by text contains:

With Range("a1:a10").FormatConditions.Add(xlTextString, TextOperator:=xlContains, String:="egg")
    With .Font
        .Bold = True
        .ColorIndex = 3
    End With
End With

Operators:

Name	Description
xlBeginsWith	Begins with a specified value.
xlContains	Contains a specified value.
xlDoesNotContain	Does not contain the specified value.
xlEndsWith	Endswith the specified value

Formatting by time period

With Range("a1:a10").FormatConditions.Add(xlTimePeriod, DateOperator:=xlToday)
    With .Font
        .Bold = True
        .ColorIndex = 3
    End With
End With

Operators:

Name
xlYesterday
xlTomorrow
xlLast7Days
xlLastWeek
xlThisWeek
xlNextWeek
xlLastMonth
xlThisMonth
xlNextMonth

Remove all conditional format in range:

Range("A1:A10").FormatConditions.Delete

Remove all conditional format in worksheet:

Cells.FormatConditions.Delete

Highlighting Duplicate Values

With Range("E1:E100").FormatConditions.AddUniqueValues
   .DupeUnique = xlDuplicate
   With .Font
       .Bold = True
       .ColorIndex = 3
   End With
End With

Highlighting Unique Values

With Range("E1:E100").FormatConditions.AddUniqueValues
   With .Font
       .Bold = True
       .ColorIndex = 3
   End With
End With

Highlighting Top 5 Values

With Range("E1:E100").FormatConditions.AddTop10
    .TopBottom = xlTop10Top
    .Rank = 5
    .Percent = False
    With .Font
        .Bold = True
        .ColorIndex = 3
    End With
End With

With Range("E1:E100").FormatConditions.AddAboveAverage
    .AboveBelow = xlAboveAverage
    With .Font
        .Bold = True
        .ColorIndex = 3
    End With
End With

Operators:

Name	Description
XlAboveAverage	Above average
XlAboveStdDev	Above standard deviation
XlBelowAverage	Below average
XlBelowStdDev	Below standard deviation
XlEqualAboveAverage	Equal above average
XlEqualBelowAverage	Equal below average

Range("a1:a10").FormatConditions.AddIconSetCondition
With Selection.FormatConditions(1)
    .ReverseOrder = False
    .ShowIconOnly = False
    .IconSet = ActiveWorkbook.IconSets(xl3Arrows)
End With

With Selection.FormatConditions(1).IconCriteria(2)
    .Type = xlConditionValuePercent
    .Value = 33
    .Operator = 7
End With

With Selection.FormatConditions(1).IconCriteria(3)
    .Type = xlConditionValuePercent
    .Value = 67
    .Operator = 7
End With

IconSet:

Name
xl3Arrows
xl3ArrowsGray
xl3Flags
xl3Signs
xl3Stars
xl3Symbols
xl3Symbols2
xl3TrafficLights1
xl3TrafficLights2
xl3Triangles
xl4Arrows
xl4ArrowsGray
xl4CRV
xl4RedToBlack
xl4TrafficLights
xl5Arrows
xl5ArrowsGray
xl5Boxes
xl5CRV
xl5Quarters

Type:

Name
xlConditionValuePercent
xlConditionValueNumber
xlConditionValuePercentile
xlConditionValueFormula

Operator:

Name	Value
xlGreater	5
xlGreaterEqual	7

Value:

Returns or sets the threshold value for an icon in a conditional format.