How to do IF on power query editor between 2 different times, both HH:MM?

Hi, alexw94 

According to your description, you want to add a column (1,0) judged by the criteria is between 00:00 - 00:15. Right?

Here are the steps you can refer to :
(1)This is my test data:

(2)And we also change the date type to "Time":

(3)Then we can add a custom column and enter this:

if [Time] >= Time.From("00:00")  and [Time] <= Time.From("00:15") then 1 else 0

(4)Then we can meet your need:

The whole M code is like this , you can put in the "Advanced Editor" to refer to :

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjCwMjRVitUBswwMYCxDI7iYBVzMDMYyNoawDK0MTSAsCysjiA5DYzArFgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Time = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Time", type time}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each if [Time] >= Time.From("00:00")  and [Time] <= Time.From("00:15") then 1 else 0)
in
    #"Added Custom"

Thank you for your time and sharing, and thank you for your support and understanding of PowerBI! 

Best Regards,

Aniya Zhang

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