How to deep copy JavaScript objects using structuredClone

May 22, 2022

Learn how to deep copy a JavaScript object with structuredClone(), the modern DOM API in Node.js 17+ that replaces hacks like JSON.parse(JSON.stringify()).

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For years and years we’ve had to use weird workarounds to do a deep clone of a JavaScript object.

Many of those were bug prone.

Like doing JSON.parse(JSON.stringify(obj)) where some types are be ignored.

Or worse, copying object properties by reference, introducing bugs down the road.

Today we have structuredClone() and it’s part of the DOM API.

It’s not part of JavaScript, it’s a DOM API.

It’s available in recent versions of all modern browsers:

Browser compatibility table showing structuredClone API support across modern browsers with 75.88% global usage

It’s also available in Node.js 17+.

Tagged: Node.js · All topics

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