#337EA7
Closest named color: Cerulean (#457B9D). oklch(56.5% 0.097 236.1), rgb(51, 126, 167).
Aa
Black text reads best on this color (4.68:1).
About this color
#337EA7 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.097 and its hue 236°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.019 away. Black text reads best on it, at 4.68:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.68:1 |
| White text | 4.48:1 |
Values
| HEX | #337EA7 |
| RGB | rgb(51, 126, 167) |
| HSL | hsl(201, 53%, 43%) |
| OKLCH | oklch(56.5% 0.097 236.1) |
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 #337EA7 | 4.48:1 | AA large text | Lc -76.3 | Fine for body text |
| Black text on #337EA7 | 4.68:1 | AA | Lc 33.2 | Non-text elements, placeholder text |
| #337EA7 text on white | 4.48:1 | AA large text | Lc 70.9 | Content text, not long reading |
| #337EA7 text on black | 4.68:1 | AA | Lc -30.8 | Non-text elements, placeholder text |
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 600.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E2EBF1
oklch(93.5% 0.013 236.6)
-
Step 200
200
#CBDCE7
oklch(88.5% 0.024 236)
-
Step 300
300
#A7C6D9
oklch(81% 0.043 235)
-
Step 400
400
#76A8C7
oklch(70.8% 0.07 236.3)
-
Step 500
500
#5092B8
oklch(63.2% 0.088 235.8)
-
Step 600
600 (this color)
#337EA7
oklch(56.5% 0.097 236.1)
-
Step 700
700
#22688D
oklch(49.2% 0.09 236.2)
-
Step 800
800
#1E5572
oklch(42.7% 0.074 235.5)
-
Step 900
900
#1F465C
oklch(37.6% 0.058 235.9)
-
Step 950
950
#132936
oklch(26.9% 0.037 236.3)
#337EA7 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) | #6A7DA9 | 0.057 |
| Deuteranopia (no green cones) | #5B72A6 | 0.048 |
| Tritanopia (no blue cones) | #00898C | 0.065 |
| Achromatopsia (no color) | #777777 | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #337EA7
#337EA7
oklch(56.5% 0.097 236.1)
- #A16639
#A16639
oklch(56.5% 0.097 56.5)
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 #337EA7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.019
- Nice Blue #107AB0 ΔE 0.027
- Stormy Blue #507B9C ΔE 0.028
- Steel Blue #4682B4 ΔE 0.029
- Dull Blue #49759C ΔE 0.030
- Flat Blue #3C73A8 ΔE 0.032
- Blue NCS #118AB2 ΔE 0.035
- Muted Blue #3B719F ΔE 0.037
Use #337EA7 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.