Why does JSON.parse(null) return null?

Question

Whenever you pass in null to JSON.parse:

console.log(JSON.parse(null))

It returns null, but I can't find any docs on why this is the case. Is there a reason why this returns null?

Other things to note:

This may be due to type conversion, as passing JSON.parse("null") also returns null, but is this specified anywhere?

Closely related: [Shouldn't JSON.parse(null) and JSON.parse(false) throw exceptions?](/q/53095713/4642212). — Sebastian Simon, Dec 25 '22 at 18:03
It’s a bit strange to post a self-answer which links to the spec while the question states _“I can't find any docs”_… — Sebastian Simon, Dec 25 '22 at 18:04
@SebastianSimon: it was to cut short a discussion under [another answer](https://stackoverflow.com/a/74914838/2159528). ;) — Louys Patrice Bessette, Dec 25 '22 at 18:06

LeoDog896 · Accepted Answer · 2022-12-25T18:00:34.283

It is converting the text to a string (null -> "null"). This is then passed to the internal JSON parser

Once it is in the parser, JSON.parse not only works with full JSON structures, but also JSON values such as number, string, and null.

Therefore, null is parsed as the null value, and returned straight back.

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