#155FD1
Closest named color: Azul (#1D5DEC). oklch(51.3% 0.19 259.8), rgb(21, 95, 209).
Aa
White text reads best on this color (5.85:1).
About this color
#155FD1 is a medium-dark, vivid blue. In OKLCH its lightness is 51%, its chroma 0.190 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Azul (#1D5DEC), ΔE 0.042 away. White text reads best on it, at 5.85:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | vivid (0.190) |
| Temperature | cool |
| Nearest name | Azul (#1D5DEC) |
| Black text | 3.58:1 |
| White text | 5.85:1 |
Values
| HEX | #155FD1 |
| RGB | rgb(21, 95, 209) |
| HSL | hsl(216, 82%, 45%) |
| OKLCH | oklch(51.3% 0.19 259.8) |
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 #155FD1 | 5.85:1 | AA | Lc -83.8 | Fine for body text |
| Black text on #155FD1 | 3.58:1 | AA large text | Lc 25.5 | Dividers and decoration only |
| #155FD1 text on white | 5.85:1 | AA | Lc 78.5 | Fine for body text |
| #155FD1 text on black | 3.58:1 | AA large text | Lc -23.3 | 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
#C6DAFC
oklch(88.4% 0.052 261.1)
-
Step 300
300
#9EC2FC
oklch(80.9% 0.091 259.8)
-
Step 400
400
#68A0FB
oklch(70.7% 0.146 259.7)
-
Step 500
500
#3E85F9
oklch(63.2% 0.188 259.8)
-
Step 600
600
#1A6BE8
oklch(55.7% 0.204 259.8)
-
Step 700
700 (this color)
#155FD1
oklch(51.3% 0.19 259.8)
-
Step 800
800
#0E49A3
oklch(42.8% 0.157 259.7)
-
Step 900
900
#153E81
oklch(37.7% 0.122 259.9)
-
Step 950
950
#0D254C
oklch(27% 0.078 259.7)
#155FD1 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) | #006DD5 | 0.035 |
| Deuteranopia (no green cones) | #005DCF | 0.010 |
| Tritanopia (no blue cones) | #007C8F | 0.145 |
| Achromatopsia (no color) | #656565 | 0.190 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155FD1
#155FD1
oklch(51.3% 0.19 259.8)
- #875F00
#875F00
oklch(51.4% 0.107 79.9)
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 #155FD1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Azul #1D5DEC ΔE 0.042
- Warm Blue #4B57DB ΔE 0.049
- Royal Blue #4169E1 ΔE 0.051
- Cerulean Blue #056EEE ΔE 0.056
- Neon Blue #4361EE ΔE 0.059
- Mid Blue #276AB3 ΔE 0.059
- Bright Blue #0165FC ΔE 0.067
- Blue Blue #2242C7 ΔE 0.068
Use #155FD1 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.