Check a Value's Data Type at Runtime in Power Query M

Inspects the actual type of a value or column, useful for debugging unexpected type errors.

Data TypesIntermediatetypedebugvalue.type

Power Query M code

let
    Source = YourTable,
    AddedTypeCheck = Table.AddColumn(Source, "ColumnType", each Value.Type([ColumnName]), type type)
in
    AddedTypeCheck

Notes

Remove this helper column once you've confirmed the type - it's a debugging step, not something to ship in a production query.

Requirements

A table with a column whose type you're unsure of.

How to use this snippet

In Power BI Desktop, choose Transform data to open Power Query, then open the Advanced Editor on a query (or start from a blank query).
Paste the snippet and replace the placeholder names (tables, columns, file paths) with your own. Check the requirements above first.
Run it through the Power Query M Formatter to tidy the layout.

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