Data Labels and Y Axis - Dynamic Format String

You can handle this directly in the Dynamic Format String by using the trailing comma trick to scale, then adding the suffix as a literal. Both the data labels and Y axis labels pick up the dynamic format per value in current Power BI versions.

Try this as the format string expression on the measure:

VAR _abs = ABS(SELECTEDMEASURE())
RETURN
SWITCH(
    TRUE(),
    _abs >= 1E6, "#,##0.00,, M",
    _abs >= 1E3, "#,##0.00, K",
    "#,##0.00"
)

Each trailing comma in the format string divides the number by 1,000, so 6,200,000 renders as 6.20 M and 54,644 as 54.64 K. If you also need a billions tier, add another branch with "#,##0.00,,, B" above the millions check.

If this helped, please mark it as the accepted solution and give it a thumbs up.

Best regards,
Shai Karmani