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#033f6f

a deep, electric blue · cool · closest name: Dark Slate Blue

RGB
3, 63, 111
HSL
207°, 95%, 22%
CMYK
97, 43, 0, 57
Luminance
0.0472

At a glance

Every number on this page in one read: what #033f6f is made of, how bright it looks, and which way it leans.

Hex
#033f6f
Hue
207°
blue
Saturation
95%
electric
Lightness
22%
deep
Brightness
44%
HSV value
Perceived
24%
weighted brightness
Luminance
0.0472
WCAG relative
Temperature
Cool
99/100 cool
Color family
Blue
Tone
Electric
Best ink
White
10.80:1
Closest name
Dark Slate Blue
ΔE2000 12.7
Where it sits
Hue207° of 360°
Saturation95%
Lightness22%
Temperature
Warm ← → Cool99% cool

Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.

Every format

HEX#033f6f
RGBrgb(3, 63, 111)
HSLhsl(207, 95%, 22%)
CMYKcmyk(97%, 43%, 0%, 57%)
LABlab(25.9 2.6 -32.6)
LCHlch(25.9 32.7 274.5)
OKLCHoklch(0.361 0.100 249.9)
Decimal212847
Display P3color(display-p3 0.012 0.247 0.435)

Copy-ready code

/* CSS */
color: #033f6f;
background-color: #033f6f;
/* Tailwind (arbitrary) */
class="text-[#033f6f] bg-[#033f6f]"
/* SCSS */
$brand: #033f6f;
/* SwiftUI */
Color(red: 0.012, green: 0.247, blue: 0.435)
/* Android */
Color.parseColor("#033f6f")
/* Flutter */
Color(0xFF033F6F)
/* Python / OpenCV (BGR) */
(111, 63, 3)

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Readable at a glance#ffffff on #033f6f · 10.80:1
Use #ffffffAAA at every size.
Aa
White text · 10.80:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 1.94:1
AA fail · AA large fail · AAA fail
Reading the other direction: #033f6f as text scores 10.80:1 on white and 1.94:1 on black.

Accessibility — WCAG contrast

Aa
#033f6f on white: 10.80:1
AA ✓ pass · AA-large · AAA
Aa
#033f6f on black: 1.94:1
AA ✗ fail · AA-large · AAA
true color
protanopia · #274271
deuteranopia · #14396E
tritanopia · #004B51

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #033f6f is pinned to step 900; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F1F8FD
#E4F1FB
#C2E1FA
#92CDFC
#5BB4FB
#259AF9
#0687EE
#0571C7
#045A9F
#033f6f
#052A48
Base = 900Lightest = 50 · #F1F8FDDarkest = 950 · #052A48
:root {
  --brand-50: #F1F8FD;
  --brand-100: #E4F1FB;
  --brand-200: #C2E1FA;
  --brand-300: #92CDFC;
  --brand-400: #5BB4FB;
  --brand-500: #259AF9;
  --brand-600: #0687EE;
  --brand-700: #0571C7;
  --brand-800: #045A9F;
  --brand-900: #033f6f;
  --brand-950: #052A48;
  --brand: #033f6f;
  --brand-ink: #ffffff;
}

Colors that work with #033f6f

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

Text on it#ffffff
White wins here
Surface#F4F8FA
Tinted page background
Border#C0D9ED
Hairlines and dividers
Muted text#4B779B
Captions on the surface
Accent#711701
Second voice, not a rival
Dark variant#03467C
Hover, pressed, headers
Light variant#E6F4FE
Selected rows, tints
Dark surface#141D24
Dark-mode background
Light mode
Everything in its place

Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.

Primary actionSecondaryBadge
Dark mode
Same hue, inverted

Lightness flips, hue holds. The accent stays the anchor in both themes.

Primary actionSecondaryAccent

How to use #033f6f

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Body text and links on white
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text on black or near-black surfaces
  • Full-page backgrounds — tiring over long sessions
  • Black text placed on it
  • Pairing with a same-lightness hue — edges vibrate

Similar colors

One move away from this hex in each direction. Every swatch is its own page.

Color relationships

The wheel positions with their names attached, so you can grab the one you actually need.

Complementary#6F3303
Analogous left#036F69
Analogous right#03096F
Split-complement 1#6F0309
Split-complement 2#6F6903
Triadic 1#6F033F
Triadic 2#3F6F03
Tetradic#69036F

RGB percentages

Red1.2%
Green24.7%
Blue43.5%

CMYK percentages

Cyan97.3%
Magenta43.2%
Yellow0.0%
Key (black)56.5%

Color previews

#033f6f text on a black background

contrast 1.94:1

Card sample

#033f6f text on a white background

contrast 10.80:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #033f6f;
Background color
Panel with #033f6f background
background-color: #033f6f;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #033f6f;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(3, 63, 111, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(3, 63, 111, 0.45);
Border & gradient
Gradient panel
border: 3px solid #033f6f;
background: linear-gradient(135deg, #033f6f, #0F036F);

Monochromatic scale

Palettes built from #033f6f

Shades — darker

Tints — lighter

Color harmonies

Nearest named colors

Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.

#033f6f in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Industries
TechnologyFinanceHealthcareEnterprise SaaS
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Sits outside most CMYK gamuts — expect a duller press result, or specify a spot ink.

#033f6f, answered

What color is #033f6f?

#033f6f is a deep electric blue, closest to Dark Slate Blue (ΔE2000 12.7). It sits at 207° on the hue wheel with 95% saturation and 22% lightness, which reads as cool.

What is the RGB value of #033f6f?

rgb(3, 63, 111) — 3 red, 63 green and 111 blue out of 255, or 1.2% / 24.7% / 43.5% by channel.

Is #033f6f a light or a dark color?

It is a dark color. Relative luminance is 0.0472 and perceived brightness is 24%, so white text on it reaches 10.80:1.

Should I use black or white text on #033f6f?

White. It scores 10.80:1 against #033f6f, versus 1.94:1 for black — AAA at any size.

What is the complementary color of #033f6f?

#6F3303 sits directly opposite on the wheel. Softer options are the split-complements #6F0309 and #6F6903, which give the same contrast with far less vibration.

What colors go well with #033f6f?

For interface work: #F4F8FA as the surface, #C0D9ED for borders, #4B779B for secondary text, #711701 as an accent and #03467C for hover and pressed states. For a palette, the analogous pair #036F69 and #03096F stays calm, while #6F3303 is the loudest partner.

What is #033f6f in CMYK for printing?

cmyk(97%, 43%, 0%, 57%). This is a screen-to-ink approximation — a color this saturated sits outside most CMYK gamuts and will print duller than it looks here.

Is #033f6f warm or cool?

Cool — it scores 99 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #03176F; nudged cooler, #012D57.

Work with #033f6f in the Color Lab