HTML Color Codes: Red to Yellow to Green
Here is nice looking gradient from green to red
/* Green - Yellow - Red */
.gradient_0 {background: #57bb8a;}
.gradient_5 {background: #63b682;}
.gradient_10 {background: #73b87e;}
.gradient_15 {background: #84bb7b;}
.gradient_20 {background: #94bd77;}
.gradient_25 {background: #a4c073;}
.gradient_30 {background: #b0be6e;}
.gradient_35 {background: #c4c56d;}
.gradient_40 {background: #d4c86a;}
.gradient_45 {background: #e2c965;}
.gradient_50 {background: #f5ce62;}
.gradient_55 {background: #f3c563;}
.gradient_60 {background: #e9b861;}
.gradient_65 {background: #e6ad61;}
.gradient_70 {background: #ecac67;}
.gradient_75 {background: #e9a268;}
.gradient_80 {background: #e79a69;}
.gradient_85 {background: #e5926b;}
.gradient_90 {background: #e2886c;}
.gradient_95 {background: #e0816d;}
.gradient_100 {background: #dd776e;}
/* Red - Yellow - Green */
.anti-gradient_100 {background: #57bb8a;}
.anti-gradient_95 {background: #63b682;}
.anti-gradient_90 {background: #73b87e;}
.anti-gradient_85 {background: #84bb7b;}
.anti-gradient_80 {background: #94bd77;}
.anti-gradient_75 {background: #a4c073;}
.anti-gradient_70 {background: #b0be6e;}
.anti-gradient_65 {background: #c4c56d;}
.anti-gradient_60 {background: #d4c86a;}
.anti-gradient_55 {background: #e2c965;}
.anti-gradient_50 {background: #f5ce62;}
.anti-gradient_45 {background: #f3c563;}
.anti-gradient_40 {background: #e9b861;}
.anti-gradient_35 {background: #e6ad61;}
.anti-gradient_30 {background: #ecac67;}
.anti-gradient_25 {background: #e9a268;}
.anti-gradient_20 {background: #e79a69;}
.anti-gradient_15 {background: #e5926b;}
.anti-gradient_10 {background: #e2886c;}
.anti-gradient_5 {background: #e0816d;}
.anti-gradient_0 {background: #dd776e;}<div class="gradient_0">0</div>
<div class="gradient_5">5</div>
<div class="gradient_10">10</div>
<div class="gradient_15">15</div>
<div class="gradient_20">20</div>
<div class="gradient_25">25</div>
<div class="gradient_30">30</div>
<div class="gradient_35">35</div>
<div class="gradient_40">40</div>
<div class="gradient_45">45</div>
<div class="gradient_50">50</div>
<div class="gradient_55">55</div>
<div class="gradient_60">60</div>
<div class="gradient_65">65</div>
<div class="gradient_70">70</div>
<div class="gradient_75">75</div>
<div class="gradient_80">80</div>
<div class="gradient_85">85</div>
<div class="gradient_90">90</div>
<div class="gradient_95">95</div>
<div class="gradient_100">100</div>The best way to do this is to understand what the hex color codes actually mean. Once you grasp this, it will become clear how to make gradients of arbitrary smoothness. The hex color codes are triplets representing the red, green and blue components of the color respectively. So for example in the color FF0000, the red component is FF, the green component is 00 and the blue component is 00. FF0000 looks red because the red component is dialed all the way up to FF and the green and blue are dialed all the way down to 00. Similarly, pure green is 00FF00 and pure blue is 0000FF. If you convert the hex numbers to decimal, you'll get a value in between 0 and 255.
So now how does one make a gradient transitioning from red to yellow to green? Easy; you take the end points, decide how many steps you want in between, and then evenly step through each of the 3 color channels to transition from one color to the next color. Below is an example going in steps of 11 hex (17 in decimal):
FF0000 <-- red
FF1100
FF2200
FF3300
FF4400
FF5500
FF6600
FF7700
FF8800
FF9900
FFAA00
FFBB00
FFCC00
FFDD00
FFEE00
FFFF00 <-- yellow
EEFF00
DDFF00
CCFF00
BBFF00
AAFF00
99FF00
88FF00
77FF00
66FF00
55FF00
44FF00
33FF00
22FF00
11FF00
00FF00 <-- green
Depending on how many colors you want to end up with, the solution is just to keep incrementing the green value by a certain amount, and then when green is maxed (FF), decrement the red value repeatedly by the same amount.
Pseudo-code:
int red = 255; //i.e. FF
int green = 0;
int stepSize = ?//how many colors do you want?
while(green < 255)
{
green += stepSize;
if(green > 255) { green = 255; }
output(red, green, 0); //assume output is function that takes RGB
}
while(red > 0)
{
red -= stepSize;
if(red < 0) { red = 0; }
output(red, green, 0); //assume output is function that takes RGB
}
Generating by hand, you can simply increment by 16, like so:
FF0000
FF1000
FF2000
FF3000
FF4000
FF5000
FF6000
FF7000
FF8000
FF9000
FFA000
FFB000
FFC000
FFD000
FFE000
FFF000
FFFF00 //max, step by 15
F0FF00 //cheat, start with a -15 to simplify the rest
E0FF00
D0FF00
C0FF00
B0FF00
A0FF00
90FF00
80FF00
70FF00
60FF00
50FF00
40FF00
30FF00
20FF00
10FF00