#377DDB
Closest named color: Water Blue (#0E87CC). oklch(59.3% 0.16 256.9), rgb(55, 125, 219).
Aa
Black text reads best on this color (5.11:1).
About this color
#377DDB is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.160 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Water Blue (#0E87CC), ΔE 0.042 away. Black text reads best on it, at 5.11:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.160) |
| Temperature | cool |
| Nearest name | Water Blue (#0E87CC) |
| Black text | 5.11:1 |
| White text | 4.10:1 |
Values
| HEX | #377DDB |
| RGB | rgb(55, 125, 219) |
| HSL | hsl(214, 69%, 54%) |
| OKLCH | oklch(59.3% 0.16 256.9) |
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 #377DDB | 4.10:1 | AA large text | Lc -73.3 | Content text, not long reading |
| Black text on #377DDB | 5.11:1 | AA | Lc 36.3 | Non-text elements, placeholder text |
| #377DDB text on white | 4.10:1 | AA large text | Lc 67.8 | Content text, not long reading |
| #377DDB text on black | 5.11:1 | AA | Lc -33.9 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF8
oklch(93.6% 0.021 254.9)
-
Step 200
200
#C9DBF4
oklch(88.6% 0.04 256.6)
-
Step 300
300
#A3C3EF
oklch(80.9% 0.072 256.4)
-
Step 400
400
#71A2E8
oklch(70.6% 0.116 257.3)
-
Step 500
500
#4A8AE1
oklch(63.2% 0.147 256.7)
-
Step 600
600 (this color)
#377DDB
oklch(59.3% 0.16 256.9)
-
Step 700
700
#1D5EB3
oklch(49% 0.15 257.1)
-
Step 800
800
#1B4E91
oklch(42.8% 0.123 256.8)
-
Step 900
900
#1C4173
oklch(37.6% 0.096 256.8)
-
Step 950
950
#112744
oklch(27.1% 0.061 256.1)
#377DDB 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) | #4E85DF | 0.032 |
| Deuteranopia (no green cones) | #3076D9 | 0.020 |
| Tritanopia (no blue cones) | #0093A1 | 0.123 |
| Achromatopsia (no color) | #7D7D7D | 0.160 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #377DDB
#377DDB
oklch(59.3% 0.16 256.9)
- #A77300
#A77300
oklch(59.4% 0.124 77.3)
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 #377DDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Water Blue #0E87CC ΔE 0.042
- Windows Blue #3778BF ΔE 0.043
- Dark Sky Blue #448EE4 ΔE 0.049
- Royal Blue #4169E1 ΔE 0.053
- Clear Blue #247AFD ΔE 0.054
- Cerulean Blue #056EEE ΔE 0.058
- Soft Blue #6488EA ΔE 0.060
- Cool Blue #4984B8 ΔE 0.063
Use #377DDB 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.