#2B37BB
Closest named color: Sapphire (#2138AB). oklch(42.6% 0.203 270.3), rgb(43, 55, 187).
Aa
White text reads best on this color (8.87:1).
About this color
#2B37BB is a dark, vivid blue. In OKLCH its lightness is 43%, its chroma 0.203 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.028 away. White text reads best on it, at 8.87:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | vivid (0.203) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.36:1 |
| White text | 8.87:1 |
Values
| HEX | #2B37BB |
| RGB | rgb(43, 55, 187) |
| HSL | hsl(235, 63%, 45%) |
| OKLCH | oklch(42.6% 0.203 270.3) |
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 #2B37BB | 8.87:1 | AAA | Lc -93.9 | Preferred for body text |
| Black text on #2B37BB | 2.36:1 | Fails | Lc 14.6 | Not readable |
| #2B37BB text on white | 8.87:1 | AAA | Lc 89.4 | Fine for body text |
| #2B37BB text on black | 2.36:1 | Fails | Lc -12.8 | Not readable |
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 800.
-
Step 50
50
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E2E9FF
oklch(93.5% 0.031 271.7)
-
Step 200
200
#CBD8FF
oklch(88.5% 0.056 270.7)
-
Step 300
300
#A9BEFF
oklch(80.9% 0.095 270.4)
-
Step 400
400
#7D99FF
oklch(70.7% 0.152 270.5)
-
Step 500
500
#5E7BFF
oklch(63.1% 0.198 270.4)
-
Step 600
600
#4458FF
oklch(55.5% 0.245 270.5)
-
Step 700
700
#3541E8
oklch(49.1% 0.245 270.3)
-
Step 800
800 (this color)
#2B37BB
oklch(42.6% 0.203 270.3)
-
Step 900
900
#253394
oklch(37.8% 0.159 270.3)
-
Step 950
950
#151F56
oklch(26.9% 0.1 270.4)
#2B37BB 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) | #0051BF | 0.058 |
| Deuteranopia (no green cones) | #0043B9 | 0.032 |
| Tritanopia (no blue cones) | #005C75 | 0.158 |
| Achromatopsia (no color) | #4A4A4A | 0.204 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B37BB
#2B37BB
oklch(42.6% 0.203 270.3)
- #614C00
#614C00
oklch(42.6% 0.087 90.4)
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 #2B37BB, closest first.
No curated palette has a color within ΔE 0.04 of #2B37BB.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.028
- Blue Blue #2242C7 ΔE 0.030
- Majorelle Blue #3F37C9 ΔE 0.035
- Indigo Blue #3A18B1 ΔE 0.053
- Blue With A Hint Of Purple #533CC6 ΔE 0.063
- Blurple #5539CC ΔE 0.068
- True Blue #010FCC ΔE 0.072
- Violet Blue #510AC9 ΔE 0.072
Use #2B37BB 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.