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---
title: offset
---
The `offset` macro will offset and join paths.
Unlike the core [`Path.join()`](/reference/api/path/join) and
[`Path.offset()`](/reference/api/path/offset) functions, the `offset`
macro can extend line ends to meet in a sharp corner and will automatically
trim useless path ends when adjacent paths in the array are intersecting.
:::note
##### Not a core-plugins macro
The `offset` macro is not provided by the [core plugins](/reference/plugins/core),
so you need to load the [path-utils plugin](/reference/plugins/path-utils)
explicitly if you want to use it.
:::
## Signature
```js
Path macro('offset', {
Array paths,
number limit,
string mode,
string class
})
```
## Example
<Example caption="An example of the offset macro">
```js
({ Point, points, Path, paths, macro, part }) => {
paths.outline = new Path()
.move(new Point(10, 30))
.line(new Point(30, 30))
.line(new Point(30, 50))
.line(new Point(50, 50))
.line(new Point(50, 70))
.line(new Point(70, 70))
.curve(new Point(55, 15), new Point(55, 15), new Point(30, 0))
paths.outline2 = new Path().move(new Point(30, 0)).line(new Point(10, 30))
paths.offset = macro('offset', {
paths: [
{ p: 'outline', offset: 10 },
{ p: 'outline2', offset: 30 },
],
}).setClass('stroke-sm mark dotted')
paths.halfCircle = new Path().move(new Point(100, 0)).circleSegment(37, new Point(200, 0)).hide()
paths.halfCircleClosed = paths.halfCircle.clone().line(new Point(200, 0)).unhide().close()
paths.halfCircleSa = macro('offset', {
paths: [{ p: 'halfCircle', offset: 10 }, null],
}).setClass('stroke-sm mark dotted')
return part
}
```
</Example>
## Configuration
| Property | Default | Type | Description |
| -------: | ---------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `paths` | | `array` | An array of paths with their offset and visibility. You can use path names in the `paths` array or reference `Path` objects directly, or insert `null` elements to create gaps. |
| `mode` | `'corner'` | `string` | Mode for joining paths. Either `'corner'` or `'cut'`. `'cut'` will join the paths directly (like `Path.join()`) without extending the corners. |
| `limit` | `null` | `number` | Allows limiting the length of extended path corners in `'corner'` mode. Prevents overly long joins on very sharp angles. Ignored if `null` or `false`. |
| `class` | `'offset'` | `string` | CSS class that is automatically applied to the resulting path. |
## Notes
The `offset` macro accepts an array of `Path` objects with their offset, like `{p: 'somePath', offset: 30}` or `{p: ['path1', 'path2'], offset: sa * 3, hidden: true}`.
For the paths in the `p` attribute, you can reference either names in the `paths` array or insert direct references to `Path` objects.
The array can contain `null` values to create gaps (e.g., for cuts on the fold or for other sections that don't need seam allowance).
By default, the `offset` macro will offset the paths in a circular fashion, joining the end
of the last path in the array to the start of the first path, creating a full outline.
If this is not desired, insert `null` elements where you want to create gaps.
You can use `offset: 0` to include paths which don't need an additional offset.
You can use `hidden: true` to omit path segments from the output, but still build corner joins as if they were there.
This can be used for cut-on-fold lines, where no seam allowance is needed.
:::note
To create a seam allowance, prefer the [`sa`](/reference/macros/sa) macro
instead of the `offset` macro. It does pretty much the same,
but the `sa` macro defaults to offsetting paths by the user defined seam allowance.
:::