How to get the aspect ratio of an image using JavaScript

I need to get the original aspect ratio of
this image

Expect to get the original aspect ratio of the image

Pass the "getAspectRatio()" function an "img.src" parameter.
The actual dimensions of the picture will be taken, after which a check will be made whether the picture is in portrait or landscape format.
As a result, the function returns aspect ratio of the image.

function getAspectRatio(image) {

    const w = image.naturalWidth;
    const h = image.naturalHeight;

    let aspectRatio;

    if (w > h) {
        aspectRatio = w / h;
    } else {
        aspectRatio = h / w;
    }

    return aspectRatio;

};

If you just need to know how many times one side is bigger than the other, then the other options suit your needs. But if you want an actual ratio, try this function and pass it an HTMLImageElement.

function aspectRatio(image) {
    const height = image.naturalHeight;
    const width = image.naturalWidth;

    const gcd = (...arr) => {
        const _gcd = (x, y) => (!y ? x : gcd(y, x % y));
        return [...arr].reduce((a, b) => _gcd(a, b));
    };

    const gcdResult = gcd(width, height);

    return `${width / gcdResult}:${height / gcdResult}`;
}

Note: I didn't write write the GCD function myself, I stole it from here.

Try this :

const aspectRatio = yourImage.naturalWidth / yourImage.naturalHeight;

console.log('Aspect ratio:', aspectRatio);