#155BB5
Closest named color: Mid Blue (#276AB3). oklch(48.3% 0.158 257.3), rgb(21, 91, 181).
Aa
White text reads best on this color (6.57:1).
About this color
#155BB5 is a medium-dark, vivid blue. In OKLCH its lightness is 48%, its chroma 0.158 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.045 away. White text reads best on it, at 6.57:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.158) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.19:1 |
| White text | 6.57:1 |
Values
| HEX | #155BB5 |
| RGB | rgb(21, 91, 181) |
| HSL | hsl(214, 79%, 40%) |
| OKLCH | oklch(48.3% 0.158 257.3) |
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 #155BB5 | 6.57:1 | AA | Lc -87.0 | Fine for body text |
| Black text on #155BB5 | 3.19:1 | AA large text | Lc 22.1 | Dividers and decoration only |
| #155BB5 text on white | 6.57:1 | AA | Lc 81.9 | Fine for body text |
| #155BB5 text on black | 3.19:1 | AA large text | Lc -19.9 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF9
oklch(93.7% 0.022 256.7)
-
Step 200
200
#C8DBF6
oklch(88.6% 0.043 257.1)
-
Step 300
300
#A2C3F2
oklch(81% 0.076 257.2)
-
Step 400
400
#6EA2EC
oklch(70.7% 0.123 257.3)
-
Step 500
500
#4689E6
oklch(63.2% 0.156 257.2)
-
Step 600
600
#2670D4
oklch(55.5% 0.17 257.5)
-
Step 700
700 (this color)
#155BB5
oklch(48.3% 0.158 257.3)
-
Step 800
800
#174D95
oklch(42.8% 0.131 257.3)
-
Step 900
900
#1A4176
oklch(37.8% 0.101 257)
-
Step 950
950
#102645
oklch(26.9% 0.064 257.3)
#155BB5 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) | #2365B8 | 0.030 |
| Deuteranopia (no green cones) | #0057B3 | 0.015 |
| Tritanopia (no blue cones) | #00717F | 0.120 |
| Achromatopsia (no color) | #5D5D5D | 0.158 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155BB5
#155BB5
oklch(48.3% 0.158 257.3)
- #7E5600
#7E5600
oklch(48.4% 0.101 77.5)
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 #155BB5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.045
- Denim Blue #3B5B92 ΔE 0.062
- French Blue #436BAD ΔE 0.065
- Dusk Blue #26538D ΔE 0.065
- Blue Blue #2242C7 ΔE 0.066
- Peacock Blue #016795 ΔE 0.067
- Dusky Blue #475F94 ΔE 0.070
- Light Navy Blue #2E5A88 ΔE 0.073
Use #155BB5 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.