# #NUM!

a number is invalid or the result is impossible to represent.

## what it means

The formula is well-formed and the arguments are numbers, but the maths cannot produce a valid result — an out-of-domain input, a value too large to represent, or an iterative calculation that never converges.

## common causes

- a domain error such as =SQRT(-1)
- a result too large or too small for the number range
- IRR/RATE-style iterative functions that fail to converge
- a negative or zero argument where the function requires a positive one

## how to fix it

- validate the input range before calling, e.g. =IF(A1<0, "", SQRT(A1))
- supply a closer starting guess to an iterative function
- rescale the calculation so intermediate values stay representable

## related

#DIV/0! · #VALUE!

## navigate

- [all error values](https://deepcalc.com/errors.md)
- [function index](https://deepcalc.com/functions.md) · [concepts](https://deepcalc.com/concepts.md) · [limits](https://deepcalc.com/limits.md)

source: https://deepcalc.com/errors/num