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index.md
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---
title: "LayoutShift: toJSON() method"
short-title: toJSON()
slug: Web/API/LayoutShift/toJSON
page-type: web-api-instance-method
status:
- experimental
browser-compat: api.LayoutShift.toJSON
---
{{APIRef("Performance API")}}{{SeeCompatTable}}
The **`toJSON()`** method of the {{domxref("LayoutShift")}} interface is a {{Glossary("Serialization","serializer")}}; it returns a JSON representation of the {{domxref("LayoutShift")}} object.
## Syntax
```js-nolint
toJSON()
```
### Parameters
None.
### Return value
A {{jsxref("JSON")}} object that is the serialization of the {{domxref("LayoutShift")}} object.
## Examples
### Using the toJSON method
In this example, calling `entry.toJSON()` returns a JSON representation of the `LayoutShift` object.
```js
const observer = new PerformanceObserver((list) => {
list.getEntries().forEach((entry) => {
console.log(entry.toJSON());
});
});
observer.observe({ type: "layout-shift", buffered: true });
```
This would log a JSON object like so:
```json
{
"name": "",
"entryType": "layout-shift",
"startTime": 246.39999999850988,
"duration": 0,
"value": 0.0071167845054842215,
"hadRecentInput": false,
"lastInputTime": 0,
"sources": [
{
"previousRect": {
"x": 917,
"y": 708,
"width": 706,
"height": 248,
"top": 708,
"right": 1623,
"bottom": 956,
"left": 917
},
"currentRect": {
"x": 693,
"y": 708,
"width": 1154,
"height": 472,
"top": 708,
"right": 1847,
"bottom": 1180,
"left": 693
}
}
]
}
```
To get a JSON string, you can use [`JSON.stringify(entry)`](/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify) directly; it will call `toJSON()` automatically.
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("JSON")}}