#155BBE
Closest named color: Mid Blue (#276AB3). oklch(49% 0.17 258.7), rgb(21, 91, 190).
Aa
White text reads best on this color (6.41:1).
About this color
#155BBE is a medium-dark, vivid blue. In OKLCH its lightness is 49%, its chroma 0.170 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.049 away. White text reads best on it, at 6.41:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.170) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.27:1 |
| White text | 6.41:1 |
Values
| HEX | #155BBE |
| RGB | rgb(21, 91, 190) |
| HSL | hsl(215, 80%, 41%) |
| OKLCH | oklch(49% 0.17 258.7) |
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 #155BBE | 6.41:1 | AA | Lc -86.4 | Fine for body text |
| Black text on #155BBE | 3.27:1 | AA large text | Lc 22.8 | Dividers and decoration only |
| #155BBE text on white | 6.41:1 | AA | Lc 81.2 | Fine for body text |
| #155BBE text on black | 3.27:1 | AA large text | Lc -20.6 | 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
#E0EBFA
oklch(93.6% 0.024 256.1)
-
Step 200
200
#C7DBF8
oklch(88.6% 0.046 257.6)
-
Step 300
300
#A1C2F6
oklch(80.8% 0.082 259.4)
-
Step 400
400
#6DA1F2
oklch(70.7% 0.132 259)
-
Step 500
500
#4487ED
oklch(63.1% 0.168 258.7)
-
Step 600
600
#236EDB
oklch(55.5% 0.182 258.6)
-
Step 700
700 (this color)
#155BBE
oklch(49% 0.17 258.7)
-
Step 800
800
#154B9A
oklch(42.7% 0.141 258.7)
-
Step 900
900
#19407A
oklch(37.8% 0.108 258.5)
-
Step 950
950
#0F2648
oklch(27.1% 0.07 258.2)
#155BBE 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) | #1166C2 | 0.029 |
| Deuteranopia (no green cones) | #0058BC | 0.012 |
| Tritanopia (no blue cones) | #007383 | 0.129 |
| Achromatopsia (no color) | #5F5F5F | 0.170 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155BBE
#155BBE
oklch(49% 0.17 258.7)
- #7F5800
#7F5800
oklch(49% 0.102 78.8)
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 #155BBE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.049
- Blue Blue #2242C7 ΔE 0.060
- Warm Blue #4B57DB ΔE 0.067
- French Blue #436BAD ΔE 0.069
- Azul #1D5DEC ΔE 0.072
- Denim Blue #3B5B92 ΔE 0.074
- Royal Blue #4169E1 ΔE 0.076
- Dusk Blue #26538D ΔE 0.079
Use #155BBE 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.