#277CB0
Closest named color: Nice Blue (#107AB0). oklch(56.1% 0.113 240.5), rgb(39, 124, 176).
Aa
Black text reads best on this color (4.59:1).
About this color
#277CB0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.113 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.012 away. Black text reads best on it, at 4.59:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.59:1 |
| White text | 4.56:1 |
Values
| HEX | #277CB0 |
| RGB | rgb(39, 124, 176) |
| HSL | hsl(203, 64%, 42%) |
| OKLCH | oklch(56.1% 0.113 240.5) |
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 #277CB0 | 4.56:1 | AA | Lc -76.8 | Fine for body text |
| Black text on #277CB0 | 4.59:1 | AA | Lc 32.7 | Non-text elements, placeholder text |
| #277CB0 text on white | 4.56:1 | AA | Lc 71.4 | Content text, not long reading |
| #277CB0 text on black | 4.59:1 | AA | Lc -30.3 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF3
oklch(93.6% 0.015 244.7)
-
Step 200
200
#C9DCEA
oklch(88.5% 0.028 239.7)
-
Step 300
300
#A4C6DF
oklch(81% 0.051 240.1)
-
Step 400
400
#71A8CF
oklch(70.8% 0.081 240.3)
-
Step 500
500
#4891C2
oklch(63.1% 0.104 240.5)
-
Step 600
600 (this color)
#277CB0
oklch(56.1% 0.113 240.5)
-
Step 700
700
#166796
oklch(49.1% 0.105 240.6)
-
Step 800
800
#16547A
oklch(42.7% 0.088 240.9)
-
Step 900
900
#1B4662
oklch(37.8% 0.067 240.5)
-
Step 950
950
#112939
oklch(27% 0.042 240.1)
#277CB0 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) | #647DB2 | 0.058 |
| Deuteranopia (no green cones) | #5170AF | 0.045 |
| Tritanopia (no blue cones) | #00898E | 0.076 |
| Achromatopsia (no color) | #767676 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #277CB0
#277CB0
oklch(56.1% 0.113 240.5)
- #A46324
#A46324
oklch(56.1% 0.113 60.5)
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 #277CB0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.012
- Flat Blue #3C73A8 ΔE 0.027
- Windows Blue #3778BF ΔE 0.031
- Steel Blue #4682B4 ΔE 0.032
- Cerulean #457B9D ΔE 0.035
- Muted Blue #3B719F ΔE 0.036
- Dull Blue #49759C ΔE 0.038
- Cool Blue #4984B8 ΔE 0.039
Use #277CB0 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.