#1B5BB1
Closest named color: Mid Blue (#276AB3). oklch(48.1% 0.151 257.5), rgb(27, 91, 177).
Aa
White text reads best on this color (6.60:1).
About this color
#1B5BB1 is a medium-dark, vivid blue. In OKLCH its lightness is 48%, its chroma 0.151 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.044 away. White text reads best on it, at 6.60:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.151) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.17:1 |
| White text | 6.60:1 |
Values
| HEX | #1B5BB1 |
| RGB | rgb(27, 91, 177) |
| HSL | hsl(214, 74%, 40%) |
| OKLCH | oklch(48.1% 0.151 257.5) |
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 #1B5BB1 | 6.60:1 | AA | Lc -87.2 | Fine for body text |
| Black text on #1B5BB1 | 3.17:1 | AA large text | Lc 21.9 | Dividers and decoration only |
| #1B5BB1 text on white | 6.60:1 | AA | Lc 82.2 | Fine for body text |
| #1B5BB1 text on black | 3.17:1 | AA large text | Lc -19.7 | 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
#E1EBF8
oklch(93.6% 0.021 254.9)
-
Step 200
200
#C9DBF4
oklch(88.6% 0.04 256.6)
-
Step 300
300
#A3C3F0
oklch(80.9% 0.073 256.9)
-
Step 400
400
#71A2E9
oklch(70.7% 0.117 257.6)
-
Step 500
500
#4B89E2
oklch(63.1% 0.149 257.6)
-
Step 600
600
#2C71D0
oklch(55.6% 0.162 257.5)
-
Step 700
700 (this color)
#1B5BB1
oklch(48.1% 0.151 257.5)
-
Step 800
800
#1B4D92
oklch(42.7% 0.126 257.6)
-
Step 900
900
#1D4174
oklch(37.7% 0.097 257.5)
-
Step 950
950
#122644
oklch(26.9% 0.062 258.3)
#1B5BB1 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) | #2964B4 | 0.028 |
| Deuteranopia (no green cones) | #0057AF | 0.017 |
| Tritanopia (no blue cones) | #00707D | 0.116 |
| Achromatopsia (no color) | #5D5D5D | 0.151 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B5BB1
#1B5BB1
oklch(48.1% 0.151 257.5)
- #7D5500
#7D5500
oklch(48.1% 0.101 77.2)
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 #1B5BB1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.044
- Denim Blue #3B5B92 ΔE 0.055
- Dusk Blue #26538D ΔE 0.059
- French Blue #436BAD ΔE 0.062
- Peacock Blue #016795 ΔE 0.062
- Dusky Blue #475F94 ΔE 0.063
- Light Navy Blue #2E5A88 ΔE 0.067
- Blue Blue #2242C7 ΔE 0.070
Use #1B5BB1 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.