# ‘e’ in javascript numbers

I need to understand the following:

when I type `4e4` in Google Chrome’s console it returns `40000`.

Can anyone help me to understand what is `e` in javascript numbers and what is the algorithm working for this?

`4e4` is a floating-point number representation.
It consists of:

1. Sign – S(+ or -)
2. Mantissa – M(some number, normalized: 1.x where x is some sequence of digits)
3. Exponent – E(represents a power of 10 that is Mantissa(M) multiplied with)

It is also a way of how floating-point numbers are stored on the system. For instance, for single-precision we get:
single-precision floating-point number representation

Together, it gives us:

`-1^S * M * p^E` where p is the basis of the numerical system

So, in common sense, p can be anything so that `4e4` could be also `4 * 5^4` if `p == 5`

As we usually work with `decimal values` `p is equal to 10`

And as was answered before, `4e4 == 4 * 10^4` (as 4 is a decimal value in this case)

‘e’ in a number like that is the same as ‘times 10 to the power of’

3.2e6 is 3.2×10^6

`4*10^4`

If the number was `4e5` this would be equal to `4*10^5`

etc. The answers/resolutions are collected from stackoverflow, are licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 .
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