jQuery round decimal to .49 or .99

Question

I'm trying to work out how to round a decimal to .49 or .99.

I have found the toFixed(2) function, but not sure how to round up or down.

Basically need to get to the closest price point, so for example X.55 would go down to X.49 and X.84 would go up to X.99.

read [similar concept](http://stackoverflow.com/questions/477892/in-jquery-whats-the-best-way-of-formatting-a-number-to-2-decimal-places) — xkeshav, Mar 25 '11 at 10:56

score 11 · Accepted Answer · answered Mar 25 '11 at 10:54

11

This doesn’t require jQuery but can be done with plain JavaScript:

Math.round(price*2)/2 - 0.01

Note to also consider the case where the number would get rounded to 0 (price > 0.25) as that would yield -0.01 in this case.

answered Mar 25 '11 at 10:54

Gumbo

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That works a treat. Nice one! I'll make sure to consider the -0.01 possibility as you point out. – diggersworld Mar 25 '11 at 11:09

score 1 · Answer 2 · answered Mar 25 '11 at 11:03

If I had a dollar for every time jQuery made things more obtuse than they needed to be...

window.round = function(num) {
    cents = (num * 100) % 100;
    if (cents >= 25 && cents < 75) {
        //round x.25 to x.74 -> x.49
        return Math.floor(num) + 0.49;
    }
    if (cents < 25) {
        //round x.00 to x.24 -> [x - 1].99
        return Math.floor(num) - 0.01;
    }
    //round x.75 to x.99 -> x.99
    return Math.floor(num) + 0.99;
};

score 0 · Answer 3 · answered Mar 25 '11 at 10:55

0

I thing you cant round/fix to a specific number, you will need to check/caclulate the value, which could mean: rounding up then subtracting 1 or rounding up and subtracting 51.

answered Mar 25 '11 at 10:55

Mark Redman

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score 0 · Answer 4 · answered Mar 25 '11 at 10:57

0

This does not require jQuery. You just need Math class from javascript also rounding off will require some addtional subtraction since rounding will give nearest decimal

answered Mar 25 '11 at 10:57

sushil bharwani

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score 0 · Answer 5 · answered May 25 '21 at 17:49

Editing aroth's answer a little bit in order to lets say we also need to round to nearest 5 multiply value

window.round = function(num) {
cents = (num * 100) % 100;
if (cents >= 25 && cents < 75) {
    //round x.25 to x.74 -> x.49
    return Math.ceil(num/5)*5  + 0.49;
}
if (cents < 25) {
    //round x.00 to x.24 -> [x - 1].99
    return Math.ceil(num/5)*5  - 0.01;
}
//round x.75 to x.99 -> x.99
return Math.ceil(num/5)*5  + 0.99;
};

jQuery round decimal to .49 or .99

5 Answers5

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