#337CB7

Closest named color: Windows Blue (#3778BF). oklch(56.8% 0.116 246.3), rgb(51, 124, 183).

Black text reads best on this color (4.70:1).

About this color

#337CB7 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.116 and its hue 246°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.019 away. Black text reads best on it, at 4.70:1.

Hue family	Blues
Lightness	medium-dark (57%)
Chroma	moderately saturated (0.116)
Temperature	cool
Nearest name	Windows Blue (#3778BF)
Black text	4.70:1
White text	4.46:1

Values

HEX	#337CB7
RGB	rgb(51, 124, 183)
HSL	hsl(207, 56%, 46%)
OKLCH	oklch(56.8% 0.116 246.3)

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 #337CB7	4.46:1	AA large text	Lc -76.1	Fine for body text
Black text on #337CB7	4.70:1	AA	Lc 33.4	Non-text elements, placeholder text
#337CB7 text on white	4.46:1	AA large text	Lc 70.7	Content text, not long reading
#337CB7 text on black	4.70:1	AA	Lc -31.0	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

#F2F6FA

oklch(97.1% 0.007 247.9)
Step 100
100

#E2EBF4

oklch(93.6% 0.016 248)
Step 200
200

#CADCEC

oklch(88.6% 0.029 244.9)
Step 300
300

#A6C5E1

oklch(81% 0.052 245.8)
Step 400
400

#75A6D2

oklch(70.7% 0.083 246.4)
Step 500
500

#4E8FC6

oklch(63.1% 0.107 246.1)
Step 600
600 (this color)

#337CB7

oklch(56.8% 0.116 246.3)
Step 700
700

#21659A

oklch(49.1% 0.108 246.3)
Step 800
800

#1E537D

oklch(42.8% 0.089 246.1)
Step 900
900

#1F4564

oklch(37.8% 0.069 245.7)
Step 950
950

#13283B

oklch(26.9% 0.045 247.5)

Export this scale for Tailwind in the Tailwind colors tool

#337CB7 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)	#617EBA	0.047
Deuteranopia (no green cones)	#4F72B6	0.034
Tritanopia (no blue cones)	#008A91	0.085
Achromatopsia (no color)	#777777	0.116