#1B5BB9
Closest named color: Mid Blue (#276AB3). oklch(48.7% 0.162 258.8), rgb(27, 91, 185).
Aa
White text reads best on this color (6.47:1).
About this color
#1B5BB9 is a medium-dark, vivid blue. In OKLCH its lightness is 49%, its chroma 0.162 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.046 away. White text reads best on it, at 6.47:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.162) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.24:1 |
| White text | 6.47:1 |
Values
| HEX | #1B5BB9 |
| RGB | rgb(27, 91, 185) |
| HSL | hsl(216, 75%, 42%) |
| OKLCH | oklch(48.7% 0.162 258.8) |
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 #1B5BB9 | 6.47:1 | AA | Lc -86.7 | Fine for body text |
| Black text on #1B5BB9 | 3.24:1 | AA large text | Lc 22.5 | Dividers and decoration only |
| #1B5BB9 text on white | 6.47:1 | AA | Lc 81.6 | Fine for body text |
| #1B5BB9 text on black | 3.24:1 | AA large text | Lc -20.3 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E1EBF9
oklch(93.7% 0.022 256.7)
-
Step 200
200
#C8DAF7
oklch(88.4% 0.045 259.9)
-
Step 300
300
#A2C2F4
oklch(80.8% 0.079 259.2)
-
Step 400
400
#6FA1EE
oklch(70.6% 0.126 258.8)
-
Step 500
500
#4988E9
oklch(63.2% 0.16 258.8)
-
Step 600
600
#2A6FD7
oklch(55.6% 0.174 258.9)
-
Step 700
700 (this color)
#1B5BB9
oklch(48.7% 0.162 258.8)
-
Step 800
800
#1A4C97
oklch(42.8% 0.134 258.8)
-
Step 900
900
#1B4078
oklch(37.7% 0.105 258.7)
-
Step 950
950
#112646
oklch(27% 0.066 258.6)
#1B5BB9 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) | #1D66BC | 0.030 |
| Deuteranopia (no green cones) | #0057B7 | 0.017 |
| Tritanopia (no blue cones) | #007281 | 0.124 |
| Achromatopsia (no color) | #5E5E5E | 0.162 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B5BB9
#1B5BB9
oklch(48.7% 0.162 258.8)
- #7E5700
#7E5700
oklch(48.6% 0.101 78.5)
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 #1B5BB9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.046
- Blue Blue #2242C7 ΔE 0.063
- French Blue #436BAD ΔE 0.064
- Denim Blue #3B5B92 ΔE 0.066
- Warm Blue #4B57DB ΔE 0.071
- Dusk Blue #26538D ΔE 0.071
- Peacock Blue #016795 ΔE 0.072
- Dusky Blue #475F94 ΔE 0.073
Use #1B5BB9 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.