#3757B1
Closest named color: Mid Blue (#276AB3). oklch(48.3% 0.148 266.2), rgb(55, 87, 177).
Aa
White text reads best on this color (6.64:1).
About this color
#3757B1 is a medium-dark, vivid blue. In OKLCH its lightness is 48%, its chroma 0.148 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.051 away. White text reads best on it, at 6.64:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.148) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.16:1 |
| White text | 6.64:1 |
Values
| HEX | #3757B1 |
| RGB | rgb(55, 87, 177) |
| HSL | hsl(224, 53%, 45%) |
| OKLCH | oklch(48.3% 0.148 266.2) |
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 #3757B1 | 6.64:1 | AA | Lc -87.5 | Fine for body text |
| Black text on #3757B1 | 3.16:1 | AA large text | Lc 21.6 | Dividers and decoration only |
| #3757B1 text on white | 6.64:1 | AA | Lc 82.5 | Fine for body text |
| #3757B1 text on black | 3.16:1 | AA large text | Lc -19.4 | 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
#F2F5FC
oklch(97% 0.01 267.4)
-
Step 100
100
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CDD9F4
oklch(88.5% 0.039 266.5)
-
Step 300
300
#ABC0F0
oklch(80.9% 0.072 266.3)
-
Step 400
400
#7F9EE8
oklch(70.6% 0.114 266.2)
-
Step 500
500
#6084E2
oklch(63.1% 0.147 266.5)
-
Step 600
600
#476CCF
oklch(55.6% 0.159 266)
-
Step 700
700 (this color)
#3757B1
oklch(48.3% 0.148 266.2)
-
Step 800
800
#2F4A91
oklch(42.8% 0.122 265.8)
-
Step 900
900
#2A3E74
oklch(37.7% 0.096 266.6)
-
Step 950
950
#182544
oklch(27% 0.061 265.4)
#3757B1 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) | #2262B4 | 0.031 |
| Deuteranopia (no green cones) | #0057AF | 0.034 |
| Tritanopia (no blue cones) | #006C7B | 0.121 |
| Achromatopsia (no color) | #5C5C5C | 0.148 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3757B1
#3757B1
oklch(48.3% 0.148 266.2)
- #775900
#775900
oklch(48.2% 0.099 85.7)
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 #3757B1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.051
- Denim Blue #3B5B92 ΔE 0.053
- Dusky Blue #475F94 ΔE 0.058
- French Blue #436BAD ΔE 0.060
- Dusk Blue #26538D ΔE 0.062
- Twilight #4E518B ΔE 0.065
- Iris #6258C4 ΔE 0.066
- Blue Blue #2242C7 ΔE 0.068
Use #3757B1 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.