#155DC3
Closest named color: Mid Blue (#276AB3). oklch(49.8% 0.174 258.7), rgb(21, 93, 195).
Aa
White text reads best on this color (6.20:1).
About this color
#155DC3 is a medium-dark, vivid blue. In OKLCH its lightness is 50%, its chroma 0.174 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.048 away. White text reads best on it, at 6.20:1.
| Hue family | Blues |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.174) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.38:1 |
| White text | 6.20:1 |
Values
| HEX | #155DC3 |
| RGB | rgb(21, 93, 195) |
| HSL | hsl(215, 81%, 42%) |
| OKLCH | oklch(49.8% 0.174 258.7) |
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 #155DC3 | 6.20:1 | AA | Lc -85.5 | Fine for body text |
| Black text on #155DC3 | 3.38:1 | AA large text | Lc 23.8 | Dividers and decoration only |
| #155DC3 text on white | 6.20:1 | AA | Lc 80.3 | Fine for body text |
| #155DC3 text on black | 3.38:1 | AA large text | Lc -21.6 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C7DBF9
oklch(88.6% 0.047 258.4)
-
Step 300
300
#A0C2F7
oklch(80.8% 0.084 259.1)
-
Step 400
400
#6BA1F4
oklch(70.7% 0.135 258.7)
-
Step 500
500
#4287EF
oklch(63.1% 0.171 258.6)
-
Step 600
600
#206EDE
oklch(55.7% 0.187 258.6)
-
Step 700
700 (this color)
#155DC3
oklch(49.8% 0.174 258.7)
-
Step 800
800
#134B9C
oklch(42.8% 0.144 258.7)
-
Step 900
900
#173F7C
oklch(37.6% 0.113 258.9)
-
Step 950
950
#0F2648
oklch(27.1% 0.07 258.2)
#155DC3 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) | #0E69C7 | 0.031 |
| Deuteranopia (no green cones) | #005AC1 | 0.012 |
| Tritanopia (no blue cones) | #007687 | 0.131 |
| Achromatopsia (no color) | #616161 | 0.174 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155DC3
#155DC3
oklch(49.8% 0.174 258.7)
- #825A00
#825A00
oklch(49.8% 0.104 78.6)
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 #155DC3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.048
- Warm Blue #4B57DB ΔE 0.061
- Blue Blue #2242C7 ΔE 0.063
- Azul #1D5DEC ΔE 0.064
- Royal Blue #4169E1 ΔE 0.068
- French Blue #436BAD ΔE 0.068
- Cerulean Blue #056EEE ΔE 0.077
- Neon Blue #4361EE ΔE 0.078
Use #155DC3 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.