Complementary Color Calculator Free tool | Plus Source Code

As a web designer, I always found myself lurking to find complementary color for a given color code.

I came across a complicated PHP script that claims to calculate the complementary color using
hue, saturation and lightness parameters – but found several errors with its output.

So i decided to write my own code. The code is simple and has nothing to do hue, saturation and lightness.
I simple uses the hexadecimal color code to derive the color codes and it is accurate.

So without much ado, here is the conversion tool.


While this code works great and gives the complementary color, this is an old code.
I have made a much more detailed color calculator to replace this code.
Check it out at:

I have tested this using random samples and this conforms with photoshop results.
However if you come across a bug or some discrepancy, please post it here as a comment.

And should you need the actual code behind this, here it goes

sorry you entered an invalid color code, 
please check your color code

'; $hexcode = mysql_real_escape_string($hexcode); $hexcode = htmlentities($hexcode); $complementarycolor = "Tit for Tat ! invalid color yields invalid results. Check your color code"; } // do all the routine form sanitization and validation // i have excluded my actual validation code for security reasons but it should work even without validation. else { //NOW the actual conversion begins // $hexcode is the six digit hex colour code we want to convert // $hexcode is the six digit hex colour code we want to convert $redhex1 = substr($hexcode,0,1); $redhex2 = substr($hexcode,1,1); $greenhex1 = substr($hexcode,2,1); $greenhex2 = substr($hexcode,3,1); $bluehex1 = substr($hexcode,4,1); $bluehex2 = substr($hexcode,5,1); $var_r1 = dechex((15-(hexdec($redhex1)))) ; $var_r2 = dechex((15- (hexdec($redhex2)))) ; $var_g1 = dechex((15-(hexdec($greenhex1)))) ; $var_g2 = dechex((15-(hexdec($greenhex2)))) ; $var_b1 = dechex((15-(hexdec($bluehex1)))); $var_b2 = dechex((15-(hexdec($bluehex2)))); $complementarycolor = $var_r1.$var_r2.$var_g1.$var_g2.$var_b1.$var_b2; } } ?>
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By Bhaskar

My name is Bhaskar. I am a CTO and a startup techno guy with 10+ years of experience startups.
Full-time coding in Python, React. Part-time coding in Haskell, Java, C.
Scientifically interested in Music, BioInformatics, Linear Algebra, Category theory, Graph theory.

What excites me: anything that has the potential to disrupt the status quo.

Looking for technical support on a startup idea ?
write at : bhaskar {-at-}

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