#155DCB
Closest named color: Azul (#1D5DEC). oklch(50.4% 0.184 259.7), rgb(21, 93, 203).
Aa
White text reads best on this color (6.06:1).
About this color
#155DCB is a medium-dark, vivid blue. In OKLCH its lightness is 50%, its chroma 0.184 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Azul (#1D5DEC), ΔE 0.051 away. White text reads best on it, at 6.06:1.
| Hue family | Blues |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.184) |
| Temperature | cool |
| Nearest name | Azul (#1D5DEC) |
| Black text | 3.45:1 |
| White text | 6.06:1 |
Values
| HEX | #155DCB |
| RGB | rgb(21, 93, 203) |
| HSL | hsl(216, 81%, 44%) |
| OKLCH | oklch(50.4% 0.184 259.7) |
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 #155DCB | 6.06:1 | AA | Lc -84.8 | Fine for body text |
| Black text on #155DCB | 3.45:1 | AA large text | Lc 24.5 | Dividers and decoration only |
| #155DCB text on white | 6.06:1 | AA | Lc 79.6 | Fine for body text |
| #155DCB text on black | 3.45:1 | AA large text | Lc -22.2 | 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 700.
-
Step 50
50
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFC
oklch(93.7% 0.026 259)
-
Step 200
200
#C6DAFB
oklch(88.4% 0.051 260.4)
-
Step 300
300
#9FC2FB
oklch(80.9% 0.09 260)
-
Step 400
400
#6AA0F9
oklch(70.7% 0.143 259.9)
-
Step 500
500
#4085F5
oklch(63% 0.182 259.7)
-
Step 600
600
#1E6BE4
oklch(55.5% 0.198 259.8)
-
Step 700
700 (this color)
#155DCB
oklch(50.4% 0.184 259.7)
-
Step 800
800
#1149A0
oklch(42.6% 0.152 259.7)
-
Step 900
900
#163E7F
oklch(37.6% 0.119 259.8)
-
Step 950
950
#0E254B
oklch(27% 0.076 259.9)
#155DCB 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) | #006BCF | 0.035 |
| Deuteranopia (no green cones) | #005BC9 | 0.010 |
| Tritanopia (no blue cones) | #00788B | 0.139 |
| Achromatopsia (no color) | #626262 | 0.184 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155DCB
#155DCB
oklch(50.4% 0.184 259.7)
- #845C00
#845C00
oklch(50.4% 0.105 79.1)
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 #155DCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Azul #1D5DEC ΔE 0.051
- Warm Blue #4B57DB ΔE 0.053
- Mid Blue #276AB3 ΔE 0.056
- Royal Blue #4169E1 ΔE 0.060
- Blue Blue #2242C7 ΔE 0.062
- Cerulean Blue #056EEE ΔE 0.066
- Neon Blue #4361EE ΔE 0.068
- French Blue #436BAD ΔE 0.075
Use #155DCB 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.