# [SOLVED] How to limit set the maximum decimal places of a number as 8 decimal places in React using javascript

## Issue

Im taking user input and trying to set the maximum amount of decimal places to 8 digits after decimal. I was researching this and I have seen solutions that tell me to do the javascript’s .toFixed() method. However, I tried it and found that it will automatically tack on about 8 zeros into the input for whatever I input into the input field. For example if I type in 5 into the field, I would get the following in the input field: `5.00000000`

This is not the goal, as I just want to limit the amount of decimal places a user can input to 8. It is fine if it is less than that.

Please see my code below. Thanks!

``````  const handleAmount = (value) => {
const numberAmount = Number(value).toFixed(8);
setAmount(numberAmount);
};

<TextField
className={classes.textField}
type="number"
onChange={e => handleAmount(e.target.value)}
value={amount}
placeholder="0.000"
inputProps={{
maxLength: 8,
step: '.01'
}}
variant="outlined" />
``````

## Solution

You could do a little trick where you multiply the number by `1e8` and then round it, then divide by `1e8`.

For example:

``````const setAmount = console.log;
const handleAmount = (value) => {
const numberAmount = Number(value);
const rounded = Math.round(numberAmount * 1e8) / 1e8;
setAmount(rounded);
};
handleAmount(10.21231123124124124142);
handleAmount(7.242);
handleAmount(80.00000000000);
handleAmount(21.00000001);``````

However, the downside is that `41.000000000` for example would be parsed as `41`.

Answered By – Arkin Solomon

Answer Checked By – Willingham (BugsFixing Volunteer)