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blue · cool

#4d55ff

a light, electric blue · cool · closest name: Slate Blue

Token name suggestion: Meadow Cobalt

RGB
77, 85, 255
HSL
237°, 100%, 65%
CMYK
70, 67, 0, 0
Luminance
0.1529

#4d55ff is a light electric blue, 237° on the wheel and 85/100 on the cool side. Put white text on it (5.17:1). As text it scores 5.17:1 on white — safe at any size. Nearest name is Slate Blue, nearest Tailwind family is indigo.

hsl(237 100% 65%)rgb(77 85 255)Base step 400AA inkCool

At a glance

Every number on this page in one read: what #4d55ff is made of, how bright it looks, and which way it leans.

Hex
#4d55ff
Hue
237°
blue
Saturation
100%
electric
Lightness
65%
light
Brightness
100%
HSV value
Perceived
45%
weighted brightness
Luminance
0.1529
WCAG relative
Temperature
Cool
85/100 cool
Color family
Blue
Tone
Electric
Best ink
White
5.17:1
Closest name
Slate Blue
ΔE2000 7
Chroma
98.7
LCH, 0–130ish
OKLCH L
0.555
perceptual lightness
Tailwind
indigo
500 · ΔE 5.3
Web-safe
#6666FF
nearest of 216
Where it sits
Hue237° of 360°
Saturation100%
Lightness65%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #4d55ff.

Temperature
Warm ← → Cool85% cool

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

Luminance by channel
Red10%
Green42%
Blue47%

Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.

Every format

HEX#4d55ff
HEX (8-digit)#4d55ffff
RGBrgb(77, 85, 255)
RGBArgba(77, 85, 255, 1)
HSLhsl(237, 100%, 65%)
HSV / HSBhsv(237, 70%, 100%)
HWBhwb(237 30% 0%)
CMYKcmyk(70%, 67%, 0%, 0%)
LABlab(46.0 50.2 -85.0)
LCHlch(46.0 98.7 300.6)
OKLCHoklch(0.555 0.246 273.0)
XYZ (D65)xyz(24.35, 15.29, 96.26)
Decimal5068287
Display P3color(display-p3 0.302 0.333 1.000)
Web-safe#6666FF

Copy-ready code

every platformclick to select
/* CSS */
color: #4d55ff;
background-color: #4d55ff;
/* CSS custom property */
--brand: #4d55ff;
/* Tailwind (arbitrary) */
class="text-[#4d55ff] bg-[#4d55ff]"
/* SCSS */
$brand: #4d55ff;
/* SwiftUI */
Color(red: 0.302, green: 0.333, blue: 1.000)
/* UIKit */
UIColor(red: 0.302, green: 0.333, blue: 1.000, alpha: 1)
/* Android XML */
<color name="brand">#4D55FF</color>
/* Android Compose */
Color(0xFF4D55FF)
/* Flutter */
Color(0xFF4D55FF)
/* Python / OpenCV (BGR) */
(255, 85, 77)
/* Python / PIL (RGB) */
(77, 85, 255)
/* Java AWT */
new Color(77, 85, 255)
/* .NET */
Color.FromArgb(255, 77, 85, 255)
/* OpenGL / Unity (0–1) */
(0.3020f, 0.3333f, 1.0000f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{77,85,255}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #4d55ff 85%, white);
border-color: color-mix(in oklab, #4d55ff 40%, transparent);
/* theme-aware in one line */
color: light-dark(#000680, #D3D4EE);
/* relative colour syntax */
--hover: hsl(from #4d55ff h s calc(l - 7));

Design tokens

The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.

css custom propertiesclick to select
:root {
  --brand-50: #F1F2FE;
  --brand-100: #E3E4FC;
  --brand-200: #C0C3FC;
  --brand-300: #8F94FF;
  --brand-400: #4d55ff;
  --brand-500: #1F29FF;
  --brand-600: #000BF5;
  --brand-700: #0009CC;
  --brand-800: #0007A3;
  --brand-900: #050A76;
  --brand-950: #030649;
  --brand: #4d55ff;
  --brand-ink: #ffffff;
  --brand-surface: #F4F5FA;
  --brand-border: #C0C2ED;
  --brand-hover: #2933FF;
  --brand-pressed: #0611FF;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #141424;
    --brand-ink: #D3D4EE;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#F1F2FE',
        100: '#E3E4FC',
        200: '#C0C3FC',
        300: '#8F94FF',
        400: '#4d55ff',
        500: '#1F29FF',
        600: '#000BF5',
        700: '#0009CC',
        800: '#0007A3',
        900: '#050A76',
        950: '#030649',
        DEFAULT: '#4d55ff',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #F1F2FE,
  '100': #E3E4FC,
  '200': #C0C3FC,
  '300': #8F94FF,
  '400': #4d55ff,
  '500': #1F29FF,
  '600': #000BF5,
  '700': #0009CC,
  '800': #0007A3,
  '900': #050A76,
  '950': #030649,
);
$brand-base: #4d55ff;
$brand-ink: #ffffff;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#F1F2FE", "$type": "color" },
      "100": { "$value": "#E3E4FC", "$type": "color" },
      "200": { "$value": "#C0C3FC", "$type": "color" },
      "300": { "$value": "#8F94FF", "$type": "color" },
      "400": { "$value": "#4d55ff", "$type": "color" },
      "500": { "$value": "#1F29FF", "$type": "color" },
      "600": { "$value": "#000BF5", "$type": "color" },
      "700": { "$value": "#0009CC", "$type": "color" },
      "800": { "$value": "#0007A3", "$type": "color" },
      "900": { "$value": "#050A76", "$type": "color" },
      "950": { "$value": "#030649", "$type": "color" }
    },
    "brandInk": { "$value": "#ffffff", "$type": "color" }
  }
}

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 #4d55ff · 5.17:1
Use #ffffffAA at every size, AAA for large text only.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 5.17:1 · recommended
AA pass · AA large pass · AAA fail
Aa
Black text · 4.06:1
AA fail · AA large pass · AAA fail
Reading the other direction: #4d55ff as text scores 5.17:1 on white and 4.06:1 on black.
Best tinted ink on it, if plain black or white feels flat: #E5E7FF at 4.24:1.

Make it accessible

A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.

The quick fox
#4d55ff · 5.17:1
AA on whitealready passes
#4d55ff
The quick fox
#242EFF · 7.22:1
AAA on white−8% L
#242EFF
The quick fox
#5C64FF · 4.72:1
AA on black+3% L
#5C64FF
The quick fox
#858BFF · 7.13:1
AAA on black+11% L
#858BFF

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #4D55FF is enough for headings on white. Non-text elements such as icons, chart strokes and focus rings also sit at 3:1 under WCAG 2.2 (1.4.11).

Accessibility — WCAG contrast

Aa
#4d55ff on white: 5.17:1
AA ✓ pass · AA-large · AAA
Aa
#4d55ff on black: 4.06:1
AA ✗ fail · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #4d55ff as text on that neutral, and that neutral as text on #4d55ff.

NeutralRatioBoth directions
White5.17:1AaAa
Slate 504.94:1AaAa
Slate 1004.72:1AaAa
Slate 2004.20:1AaAa
Slate 3003.48:1AaAa
Slate 4002.02:1AaAa
Slate 5001.09:1AaAa
Slate 6001.46:1AaAa
Slate 7002.00:1AaAa
Slate 8002.83:1AaAa
Slate 9003.45:1AaAa
Black4.06:1AaAa
Colour vision deficiency
true color
protanopia · #0075FF
deuteranopia · #0065FC
tritanopia · #0083A3

Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #4d55ff is pinned to step 400; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F1F2FE
#E3E4FC
#C0C3FC
#8F94FF
#4d55ff
#1F29FF
#000BF5
#0009CC
#0007A3
#050A76
#030649
Base = 400Lightest = 50 · #F1F2FEDarkest = 950 · #030649Text step on white = 400
Perceptual ramp — OKLCH

The same eleven steps expressed in OKLCH, where equal lightness numbers actually look equally spaced. HSL ramps go muddy in the yellows and washed out in the blues; this one does not. Modern browsers render it natively — the hex ramp above is the fallback.

50100200300400500600700800900950
oklch tokensclick to select
:root {
  --brand-50: oklch(0.97 0.061 273.0);
  --brand-100: oklch(0.94 0.098 273.0);
  --brand-200: oklch(0.88 0.148 273.0);
  --brand-300: oklch(0.80 0.192 273.0);
  --brand-400: oklch(0.72 0.226 273.0);
  --brand-500: oklch(0.64 0.246 273.0);
  --brand-600: oklch(0.56 0.246 273.0);
  --brand-700: oklch(0.48 0.231 273.0);
  --brand-800: oklch(0.40 0.207 273.0);
  --brand-900: oklch(0.32 0.172 273.0);
  --brand-950: oklch(0.24 0.135 273.0);
}

Colors that work with #4d55ff

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#F4F5FA
Tinted page background
Border#C0C2ED
Hairlines and dividers
Muted text#4B4E9B
Captions on the surface
Accent#CC8F00
Second voice, not a rival
Dark variant#000680
Hover, pressed, headers
Light variant#E5E7FF
Selected rows, tints
Dark surface#141424
Dark-mode background
Hover#2933FF
One step down in lightness
Pressed#0611FF
Two steps down
Disabled#D7D8E5
Chroma pulled out
Focus ring#6169FF
Offset from the fill so it reads
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

In real components

The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.

Buttons and states
Save changesHoverPressedDisabled
OutlineSubtleLinkFocused
Form field
you@company.com

Focus ring uses the light variant so the field still reads as one shape.

Send me product updates
Notice
Your export is ready

The file stays available for seven days. Download it before it expires.

NewBetaDraft
Data
Storage used68%
Acme LtdActive
NorthwindTrial
GlobexActive

How to use #4d55ff

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
  • Card and section backgrounds
  • Brand accents, badges and data highlights
Use with care
  • Full-page backgrounds — tiring over long sessions
  • White text placed on it
  • Pairing with a same-lightness hue — edges vibrate
Minimum size as text on white
Any size
Safe as a fill behind white type
Yes
Safe as a 1px border on white
Yes

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

trustedcalmcompetentcorporate

The default of institutions for a reason: blue is read as stable and safe across nearly every culture that has been surveyed.

At this chroma the association is amplified — it will dominate anything placed beside it, so give it space and use it sparingly. The lightness keeps it airy and approachable.

Worth knowing

It is also the most crowded hue on the web. Distinctiveness has to come from your other choices.

Reads as
  • FormalityLow
  • EnergyHigh
  • Weight35/100
  • TemperatureCool
  • ApproachabilityReserved

Colour associations are cultural and vary by market. Treat these as a starting point for a conversation with your audience, not a finding about them.

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#FFF74D
Analogous left#4DAEFF
Analogous right#9E4DFF
Split-complement 1#FF9E4D
Split-complement 2#AEFF4D
Triadic 1#FF4D55
Triadic 2#55FF4D
Tetradic#FF4DAE
On the wheel
Base+30°−30°+120°+240°+180°237°

#4d55ff sits at 237°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red30.2%
Green33.3%
Blue100.0%
R · 0–255
77
0x4d
G · 0–255
85
0x55
B · 0–255
255
0xff

CMYK percentages

Cyan69.8%
Magenta66.7%
Yellow0.0%
Key (black)0.0%

Total ink coverage is 137%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#4d55ff text on a black background

contrast 4.06:1

Card sample

#4d55ff text on a white background

contrast 5.17:1

Card sample

#4d55ff on grey

4.72:1

#4d55ff on its own surface

4.75:1

#4d55ff on its dark surface

3.51:1

CSS3 live lab

Text font color

The quick brown fox

color: #4d55ff;
Background color
Panel with #4d55ff background
background-color: #4d55ff;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #4d55ff;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(77, 85, 255, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(77, 85, 255, 0.45);
Border & gradient
Gradient panel
border: 3px solid #4d55ff;
background: linear-gradient(135deg, #4d55ff, #BC4DFF);
Gradient text

Gradient headline

background: linear-gradient(90deg, #4d55ff, #E84DFF);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #4d55ff;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #4d55ff;
caret-color: #4d55ff;
Left rule
Pull quote or callout
border-left: 4px solid #4d55ff;
Ring + tint
Selected chip
background: #E5E7FF;
box-shadow: inset 0 0 0 2px #4d55ff;
Conic badge
68%
background: conic-gradient(#4d55ff 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #4d55ff over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.

Bottom row of hexes is the flattened result over white — use those when a design tool refuses transparency, or when you need a solid fallback.

alpha in every syntaxclick to select
rgba(77, 85, 255, 0.5)
rgb(77 85 255 / 50%)
#4d55ff80
hsl(237 100% 65% / 50%)
color-mix(in srgb, #4d55ff 50%, transparent)
Alpha8-digit hexFlat on white
10%#4d55ff1a#EDEEFF
20%#4d55ff33#DBDDFF
40%#4d55ff66#B8BBFF
60%#4d55ff99#9499FF
80%#4d55ffcc#7177FF

Gradients from #4d55ff

Six recipes, each built from this hex and shown with the exact CSS that produced it.

Elevation
Same hue, three lightnesses — safe anywhere
background: linear-gradient(135deg, #8A8FFF, #4d55ff 45%, #000680);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #4d55ff, #C12EFF);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #4d55ff, #FFF74D);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #A9ADFF 0%, #4d55ff 45%, #000680 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #F4F5FA, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #80D0FF 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #BB6CFF 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #000680 0%, transparent 65%), #4d55ff;

Monochromatic scale

Palettes built from #4d55ff

Shades — darker

Tints — lighter

Tones — desaturated

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.

#4d55ff 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
SurfacesBadgesHighlightsEmpty states
Print note

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

On screens

Holds up across typical panel gamma. Still worth checking on an uncalibrated laptop, where mid-tones shift most.

In dark mode

Too dim on dark surfaces at 4.06:1 — lift it to #5C64FF for body text, or reserve it for fills.

Explore nearby colors

Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.

#4d55ff, answered

What color is #4d55ff?

#4d55ff is a light electric blue, closest to Slate Blue (ΔE2000 7). It sits at 237° on the hue wheel with 100% saturation and 65% lightness, which reads as cool.

What is the RGB value of #4d55ff?

rgb(77, 85, 255) — 77 red, 85 green and 255 blue out of 255, or 30.2% / 33.3% / 100% by channel.

What is #4d55ff in HSL and HSV?

hsl(237, 100%, 65%) and hsv(237, 70%, 100%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #4d55ff a light or a dark color?

It is a dark color. Relative luminance is 0.1529 and perceived brightness is 45%, so white text on it reaches 5.17:1.

Should I use black or white text on #4d55ff?

White. It scores 5.17:1 against #4d55ff, versus 4.06:1 for black — AA at any size.

Is #4d55ff accessible on a white background?

#4d55ff on white scores 5.17:1, which clears AA at every size but not AAA.

What is the complementary color of #4d55ff?

#FFF74D sits directly opposite on the wheel. Softer options are the split-complements #FF9E4D and #AEFF4D, which give the same contrast with far less vibration.

What colors go well with #4d55ff?

For interface work: #F4F5FA as the surface, #C0C2ED for borders, #4B4E9B for secondary text, #CC8F00 as an accent and #000680 for hover and pressed states. For a palette, the analogous pair #4DAEFF and #9E4DFF stays calm, while #FFF74D is the loudest partner.

What is #4d55ff in CMYK for printing?

cmyk(70%, 67%, 0%, 0%). 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 #4d55ff warm or cool?

Cool — it scores 85 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #864DFF; nudged cooler, #4D7CFF.

Which Tailwind color is closest to #4d55ff?

The indigo family — its 500 step is #6366f1, ΔE2000 5.3 away. That is a visible difference, so define #4d55ff as a custom token rather than reaching for the built-in.

How do I use #4d55ff in Tailwind CSS?

Inline it as an arbitrary value with bg-[#4d55ff] or text-[#4d55ff], or register the whole ramp under theme.extend.colors.brand so you get bg-brand-500 and friends. The generated 50–950 scale on this page is ready to paste into your config.

What is #4d55ff with 50% opacity?

rgba(77, 85, 255, 0.5), or #4d55ff80 in eight-digit hex. Over white that composites to #A6AAFF; over black, #272B80.

Is #4d55ff a web-safe color?

No. The nearest web-safe colour is #6666FF, ΔE2000 5.6 away. The palette only matters for legacy displays and some email clients now.

What does the color #4d55ff mean?

As a blue, it reads trusted, calm, competent. The default of institutions for a reason: blue is read as stable and safe across nearly every culture that has been surveyed. At this chroma the effect is amplified — it will dominate whatever sits beside it.

What gradient works with #4d55ff?

The safest is same-hue elevation: linear-gradient(135deg, #8A8FFF, #4d55ff 45%, #000680). For more colour, a short hue run to #C12EFF keeps it rich without turning muddy.

Work with #4d55ff in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #4d55ff at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.