#377A99
Closest named color: Cerulean (#457B9D). oklch(54.9% 0.083 231), rgb(55, 122, 153).
Aa
White text reads best on this color (4.76:1).
About this color
#377A99 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.083 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.015 away. White text reads best on it, at 4.76:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.083) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.40:1 |
| White text | 4.76:1 |
Values
| HEX | #377A99 |
| RGB | rgb(55, 122, 153) |
| HSL | hsl(199, 47%, 41%) |
| OKLCH | oklch(54.9% 0.083 231) |
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 #377A99 | 4.76:1 | AA | Lc -78.3 | Fine for body text |
| Black text on #377A99 | 4.40:1 | AA large text | Lc 31.2 | Non-text elements, placeholder text |
| #377A99 text on white | 4.76:1 | AA | Lc 72.9 | Content text, not long reading |
| #377A99 text on black | 4.40:1 | AA large text | Lc -28.8 | Dividers and decoration only |
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
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBF0
oklch(93.5% 0.011 234.8)
-
Step 200
200
#CCDCE4
oklch(88.5% 0.02 229.1)
-
Step 300
300
#A9C6D5
oklch(81% 0.038 230.3)
-
Step 400
400
#7AA8BF
oklch(70.7% 0.06 230.3)
-
Step 500
500
#5692AF
oklch(63.1% 0.076 230.6)
-
Step 600
600 (this color)
#377A99
oklch(54.9% 0.083 231)
-
Step 700
700
#2B6884
oklch(49% 0.077 231.1)
-
Step 800
800
#25556C
oklch(42.7% 0.064 231.8)
-
Step 900
900
#234657
oklch(37.6% 0.05 231.2)
-
Step 950
950
#152933
oklch(26.9% 0.032 231.4)
#377A99 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) | #6A789B | 0.056 |
| Deuteranopia (no green cones) | #5D6E99 | 0.050 |
| Tritanopia (no blue cones) | #008384 | 0.055 |
| Achromatopsia (no color) | #737373 | 0.083 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #377A99
#377A99
oklch(54.9% 0.083 231)
- #986343
#986343
oklch(55% 0.083 51.4)
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 #377A99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.015
- Dull Blue #49759C ΔE 0.022
- Stormy Blue #507B9C ΔE 0.025
- Ocean #017B92 ΔE 0.028
- Metallic Blue #4F738E ΔE 0.029
- Muted Blue #3B719F ΔE 0.031
- Sea Blue #047495 ΔE 0.033
- Flat Blue #3C73A8 ΔE 0.036
Use #377A99 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.