#377AE4
Closest named color: Clear Blue (#247AFD). oklch(59.3% 0.175 259.4), rgb(55, 122, 228).
Aa
Black text reads best on this color (5.06:1).
About this color
#377AE4 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.175 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Clear Blue (#247AFD), ΔE 0.039 away. Black text reads best on it, at 5.06:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.175) |
| Temperature | cool |
| Nearest name | Clear Blue (#247AFD) |
| Black text | 5.06:1 |
| White text | 4.14:1 |
Values
| HEX | #377AE4 |
| RGB | rgb(55, 122, 228) |
| HSL | hsl(217, 76%, 55%) |
| OKLCH | oklch(59.3% 0.175 259.4) |
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 #377AE4 | 4.14:1 | AA large text | Lc -73.6 | Content text, not long reading |
| Black text on #377AE4 | 5.06:1 | AA | Lc 36.0 | Non-text elements, placeholder text |
| #377AE4 text on white | 4.14:1 | AA large text | Lc 68.1 | Content text, not long reading |
| #377AE4 text on black | 5.06:1 | AA | Lc -33.6 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E1EBFA
oklch(93.7% 0.023 258.4)
-
Step 200
200
#C8DAF7
oklch(88.4% 0.045 259.9)
-
Step 300
300
#A3C2F4
oklch(80.9% 0.079 259.9)
-
Step 400
400
#70A1EF
oklch(70.7% 0.127 259.4)
-
Step 500
500
#4A87E9
oklch(63.1% 0.161 259.5)
-
Step 600
600 (this color)
#377AE4
oklch(59.3% 0.175 259.4)
-
Step 700
700
#1E5CBB
oklch(49.2% 0.163 259.3)
-
Step 800
800
#1B4B97
oklch(42.6% 0.135 259.5)
-
Step 900
900
#1C4078
oklch(37.7% 0.104 259.1)
-
Step 950
950
#112646
oklch(27% 0.066 258.6)
#377AE4 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) | #4085E8 | 0.031 |
| Deuteranopia (no green cones) | #0F75E2 | 0.026 |
| Tritanopia (no blue cones) | #0093A4 | 0.136 |
| Achromatopsia (no color) | #7D7D7D | 0.175 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #377AE4
#377AE4
oklch(59.3% 0.175 259.4)
- #A57400
#A57400
oklch(59.4% 0.123 79.2)
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 #377AE4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Clear Blue #247AFD ΔE 0.039
- Royal Blue #4169E1 ΔE 0.042
- Cerulean Blue #056EEE ΔE 0.045
- Dark Sky Blue #448EE4 ΔE 0.056
- Windows Blue #3778BF ΔE 0.057
- Water Blue #0E87CC ΔE 0.057
- Cornflower #6A79F7 ΔE 0.061
- Soft Blue #6488EA ΔE 0.062
Use #377AE4 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.