Length Unit Converter in Excel

From To

0.1

Add-in Formula =PO.UnitConverter(1, "cm", "dm")

Excel Lambda

=LAMBDA(x,
  LET(
    ratio, 0.1,
    x * ratio
  )
)(1)

Category Lambda

=LAMBDA(x, from, to,
  LET(
    f, SWITCH(from,
      "m", 1,
      "cm", 0.01,
      "dam", 10,
      "dm", 0.1,
      "ft", 0.3048,
      "in", 0.0254,
      "km", 1000,
      "mi", 1609.344,
      "mm", 0.001,
      "yd", 0.9144),
    t, SWITCH(to,
      "m", 1,
      "cm", 0.01,
      "dam", 10,
      "dm", 0.1,
      "ft", 0.3048,
      "in", 0.0254,
      "km", 1000,
      "mi", 1609.344,
      "mm", 0.001,
      "yd", 0.9144),
    x * f / t
  )
)(1, "cm", "dm")

How to save as a reusable Excel function

LAMBDA is a built-in Excel feature (Microsoft 365) that lets you create custom functions without VBA. The formulas above work as-is when pasted into a cell.

To save a LAMBDA as a reusable named function:

Go to Formulas → Name Manager → New
Enter a name, e.g. ConvertLength
In Refers to, paste the LAMBDA formula without the trailing invocation (...)
Click OK

Now use =ConvertLength(1, "cm", "dm") anywhere in your workbook — no add-in required.

Conversion Factors (base: m)

Unit	Name	Factor
m	metre	1
cm	centimetre	0.01
dam	dekametre	10
dm	decimetre	0.1
ft	foot	0.3048
in	inch	0.0254
km	kilometre	1000
mi	mile	1609.344
mm	millimetre	0.001
yd	yard	0.9144