Add opacity to hex representation of color

Question

I have a color code, for example #EB5757 which is a kind of red. I want to add opacity to it 0.15 or 15%. After looking on this question I saw in the accepted answer that for 15% one must add 26 at the beginning.

So I did it: #26EB5757 but now the resulted color is not a red with opacity but a green. I'm using this in Javascript/React if this information is useful.

style = {backgroundColor: '#26EB5757'}

Any ideas on how to set that original red color to be opaque?

Answer 1

8 digit hexadecimal color notation in CSS has the following format:

#RRGGBBAA

RR - red
GG - green
BB - blue
AA - alpha

You should use:

#EB575726 (for your 15% red)

Answer 2

I guess you can use convertor to get actual RGB representation of that HEX. You may try this one

Then you can simple add your opacity into rgba like this use backgroundColor: rgba(235,87,87, 0.15)