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#3f85ba

a balanced, vivid blue · cool · closest name: Steel Blue

RGB
63, 133, 186
HSL
206°, 49%, 49%
CMYK
66, 29, 0, 27
Luminance
0.2138

At a glance

Every number on this page in one read: what #3f85ba is made of, how bright it looks, and which way it leans.

Hex
#3f85ba
Hue
206°
blue
Saturation
49%
vivid
Lightness
49%
balanced
Brightness
73%
HSV value
Perceived
49%
weighted brightness
Luminance
0.2138
WCAG relative
Temperature
Cool
98/100 cool
Color family
Blue
Tone
Vivid
Best ink
Black
5.28:1
Closest name
Steel Blue
ΔE2000 1.5
Where it sits
Hue206° of 360°
Saturation49%
Lightness49%
Temperature
Warm ← → Cool98% 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#3f85ba
RGBrgb(63, 133, 186)
HSLhsl(206, 49%, 49%)
CMYKcmyk(66%, 29%, 0%, 27%)
LABlab(53.4 -5.1 -34.3)
LCHlch(53.4 34.6 261.5)
OKLCHoklch(0.595 0.107 244.0)
Decimal4163002
Display P3color(display-p3 0.247 0.522 0.729)

Copy-ready code

/* CSS */
color: #3f85ba;
background-color: #3f85ba;
/* Tailwind (arbitrary) */
class="text-[#3f85ba] bg-[#3f85ba]"
/* SCSS */
$brand: #3f85ba;
/* SwiftUI */
Color(red: 0.247, green: 0.522, blue: 0.729)
/* Android */
Color.parseColor("#3f85ba")
/* Flutter */
Color(0xFF3F85BA)
/* Python / OpenCV (BGR) */
(186, 133, 63)

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#000000 on #3f85ba · 5.28:1
Use #000000AA at every size, AAA for large text only.
Aa
White text · 3.98:1
AA fail · AA large pass · AAA fail
Aa
Black text · 5.28:1 · recommended
AA pass · AA large pass · AAA fail
Reading the other direction: #3f85ba as text scores 3.98:1 on white and 5.28:1 on black.

Accessibility — WCAG contrast

Aa
#3f85ba on white: 3.98:1
AA ✗ fail · AA-large · AAA
Aa
#3f85ba on black: 5.28:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #6D86BC
deuteranopia · #5C7AB9
tritanopia · #009297

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #3f85ba is pinned to step 600; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F4F8FA
#EAF1F6
#CFE0EC
#ABCBE3
#81B1D4
#5796C6
#3f85ba
#346D98
#29577A
#214159
#152938
Base = 600Lightest = 50 · #F4F8FADarkest = 950 · #152938
:root {
  --brand-50: #F4F8FA;
  --brand-100: #EAF1F6;
  --brand-200: #CFE0EC;
  --brand-300: #ABCBE3;
  --brand-400: #81B1D4;
  --brand-500: #5796C6;
  --brand-600: #3f85ba;
  --brand-700: #346D98;
  --brand-800: #29577A;
  --brand-900: #214159;
  --brand-950: #152938;
  --brand: #3f85ba;
  --brand-ink: #000000;
}

Colors that work with #3f85ba

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

Text on it#000000
Black wins here
Surface#F4F8FA
Tinted page background
Border#C2D9EA
Hairlines and dividers
Muted text#4B789B
Captions on the surface
Accent#BF523A
Second voice, not a rival
Dark variant#20445F
Hover, pressed, headers
Light variant#ECF3F9
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 #3f85ba

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

Works well for
  • Headings from 24px up on white
  • Text and icons on dark surfaces
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Brand accents, badges and data highlights
Use with care
  • Small text on white — under 4.5:1
  • Full-page backgrounds — tiring over long sessions
  • 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#BA743F
Analogous left#3FBAB2
Analogous right#3F47BA
Split-complement 1#BA3F47
Split-complement 2#BAB23F
Triadic 1#BA3F85
Triadic 2#85BA3F
Tetradic#B23FBA

RGB percentages

Red24.7%
Green52.2%
Blue72.9%

CMYK percentages

Cyan66.1%
Magenta28.5%
Yellow0.0%
Key (black)27.1%

Color previews

#3f85ba text on a black background

contrast 5.28:1

Card sample

#3f85ba text on a white background

contrast 3.98:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #3f85ba;
Background color
Panel with #3f85ba background
background-color: #3f85ba;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #3f85ba;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(63, 133, 186, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(63, 133, 186, 0.45);
Border & gradient
Gradient panel
border: 3px solid #3f85ba;
background: linear-gradient(135deg, #3f85ba, #4B3FBA);

Monochromatic scale

Palettes built from #3f85ba

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.

#3f85ba 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

Converts to four-color process without much drama. Proof it anyway.

#3f85ba, answered

What color is #3f85ba?

#3f85ba is a balanced vivid blue, closest to Steel Blue (ΔE2000 1.5). It sits at 206° on the hue wheel with 49% saturation and 49% lightness, which reads as cool.

What is the RGB value of #3f85ba?

rgb(63, 133, 186) — 63 red, 133 green and 186 blue out of 255, or 24.7% / 52.2% / 72.9% by channel.

Is #3f85ba a light or a dark color?

It is a mid-tone. Relative luminance is 0.2138 and perceived brightness is 49%, so black text on it reaches 5.28:1.

Should I use black or white text on #3f85ba?

Black. It scores 5.28:1 against #3f85ba, versus 3.98:1 for white — AA at any size.

What is the complementary color of #3f85ba?

#BA743F sits directly opposite on the wheel. Softer options are the split-complements #BA3F47 and #BAB23F, which give the same contrast with far less vibration.

What colors go well with #3f85ba?

For interface work: #F4F8FA as the surface, #C2D9EA for borders, #4B789B for secondary text, #BF523A as an accent and #20445F for hover and pressed states. For a palette, the analogous pair #3FBAB2 and #3F47BA stays calm, while #BA743F is the loudest partner.

What is #3f85ba in CMYK for printing?

cmyk(66%, 29%, 0%, 27%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #3f85ba warm or cool?

Cool — it scores 98 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #3F58BA; nudged cooler, #3671A9.

Work with #3f85ba in the Color Lab