---
title: utils.pctBasedOn()
---
The `utils.pctBasedOn()` function is a helper function to be used when
configuring [snapped percentage
options](/reference/api/part/config/options/pct/snap).
## Signature
```js
object utils.pctBasedOn(String measurement)
```
## Example
```js
const options = {
example: {
pct: 12,
min: 5,
max: 18,
snap: 3,
...pctBasedOn('chest')
}
}
```
## Notes
This will return an object with `toAbs` and `fromAbs` properties that calculate
the option's absolute and relative values based on a measurement. Refer to
[snapped percentage options](/reference/api/part/config/options/pct/snap) for
more details.