#51838B
Closest named color: Grey Blue (#647D8E). oklch(57.8% 0.055 208.6), rgb(81, 131, 139).
Aa
Black text reads best on this color (4.96:1).
About this color
#51838B is a medium-dark, muted teal or cyan. In OKLCH its lightness is 58%, its chroma 0.055 and its hue 209°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.029 away. Black text reads best on it, at 4.96:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (58%) |
| Chroma | muted (0.055) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 4.96:1 |
| White text | 4.22:1 |
Values
| HEX | #51838B |
| RGB | rgb(81, 131, 139) |
| HSL | hsl(188, 26%, 43%) |
| OKLCH | oklch(57.8% 0.055 208.6) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #51838B | 4.22:1 | AA large text | Lc -74.6 | Content text, not long reading |
| Black text on #51838B | 4.96:1 | AA | Lc 35.0 | Non-text elements, placeholder text |
| #51838B text on white | 4.22:1 | AA large text | Lc 69.1 | Content text, not long reading |
| #51838B text on black | 4.96:1 | AA | Lc -32.6 | Non-text elements, placeholder text |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 600.
-
Step 50
50
#F3F6F7
oklch(97.1% 0.003 219.5)
-
Step 100
100
#E5EBEC
oklch(93.6% 0.007 208.8)
-
Step 200
200
#CFDCDE
oklch(88.5% 0.014 207.9)
-
Step 300
300
#AFC5C9
oklch(80.8% 0.025 209.8)
-
Step 400
400
#84A8AE
oklch(70.7% 0.04 208.8)
-
Step 500
500
#65929A
oklch(63% 0.05 209.8)
-
Step 600
600 (this color)
#51838B
oklch(57.8% 0.055 208.6)
-
Step 700
700
#3B6970
oklch(49.1% 0.052 208.1)
-
Step 800
800
#32565B
oklch(42.8% 0.042 207)
-
Step 900
900
#2C474B
oklch(37.8% 0.033 207.6)
-
Step 950
950
#1A292C
oklch(26.9% 0.021 211.4)
#51838B with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #7B7F8C | 0.053 |
| Deuteranopia (no green cones) | #72788B | 0.049 |
| Tritanopia (no blue cones) | #388785 | 0.028 |
| Achromatopsia (no color) | #7B7B7B | 0.055 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51838B
#51838B
oklch(57.8% 0.055 208.6)
- #986E67
#986E67
oklch(57.9% 0.055 29.5)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #51838B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.029
- Battleship Grey #6B7C85 ΔE 0.034
- Steel Grey #6F828A ΔE 0.036
- Slate Gray #708090 ΔE 0.040
- Stormy Blue #507B9C ΔE 0.041
- Dusty Teal #4C9085 ΔE 0.043
- Cerulean #457B9D ΔE 0.044
- Steel #738595 ΔE 0.046
Use #51838B in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.