#666757

#666757

Color Values

HEX

#666757

RGB

102, 103, 87

HSL

63.7, 8.4%, 37.3%

HSV

63.7, 15.5%, 40.4%

CMYK

1.0%, 0.0%, 15.5%, 59.6%

OKLCH

0.5081 0.0245 110.2

Properties

Cool Dark Nearest: RAL 7023 Concrete Grey

Color Harmonies

Complementary

#666757

#585767

Analogous

#676057

#5E6757

#666757

Triadic

#666757

#576667

#675766

Split Complementary

#666757

#575E67

#605767

Tetradic

#666757

#576760

#585767

#67575E

Color Blindness Simulation

Original

#666757

Protanopia

#66665B

Deuteranopia

#66665C

Tritanopia

#665E5F

Achromatopsia

#666666

CSS Usage

background-color: #666757;
color: #666757;
border-color: #666757;
Nearest Tailwind: Stone 500 #78716C

Tailwind Shades

50
#F8F8F7
100
#EEEEEC
200
#DEDED8
300
#C6C7BD
400
#A8A999
500
#898A75
600
#6E6F5D
700
#58584B
800
#44453A
900
#34342D
950
#21211C

Contrast Checker

Text on white

5.76:1

AA Pass AAA Fail

Text on black

3.64:1

AA Fail AAA Fail

Related Articles

Tutorials

Building a Color Picker Web Component from Scratch

Feb 20, 2026
Tutorials

Web Color Performance: Gradients, Shadows, and Filters

Feb 19, 2026
Tutorials

Tailwind CSS Colors: Complete Shade System Guide

Feb 19, 2026