How to get file size from file path with js?

Question

I want to get the size of a file from this path:

my-path/filename

How can I get the size of this file?

Is that a file path or a URL? It looks like a URL with the schema missing, but the answer will be very different if it is one. — Quentin
– Quentin, Commented Feb 7, 2023 at 15:10
Why are you marking the file path / URL as a quote? Who are you quoting? Please take care to format your questions correctly. — Quentin
– Quentin, Commented Feb 7, 2023 at 15:10
You'll need to make a request. If the server reports back a correct Content-Length header, a HEAD request will probably do; otherwise you'll have to request the full thing. — C3roe
– C3roe, Commented Feb 7, 2023 at 15:10

NetByMatt · Accepted Answer · 2023-02-07 15:12:47Z

2

Use the fetch() method and only set the request method to HEAD.

    const fetchResponse = await fetch(src, { method: 'HEAD' });
    const size = fetchResponse.headers.get('content-length');

Beware, it will return a number represented as a string.

answered Feb 7, 2023 at 15:12

NetByMatt

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2 Comments

you can auto convert to a number by putting a + before fetchResponse. const size = +fetchResponse.headers.get('content-length');

but when using the + be aware of values like null, true, false and such.