#2579DF
Closest named color: Cerulean Blue (#056EEE). oklch(58.2% 0.174 256), rgb(37, 121, 223).
Aa
Black text reads best on this color (4.87:1).
About this color
#2579DF is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.174 and its hue 256°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean Blue (#056EEE), ΔE 0.041 away. Black text reads best on it, at 4.87:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.174) |
| Temperature | cool |
| Nearest name | Cerulean Blue (#056EEE) |
| Black text | 4.87:1 |
| White text | 4.30:1 |
Values
| HEX | #2579DF |
| RGB | rgb(37, 121, 223) |
| HSL | hsl(213, 74%, 51%) |
| OKLCH | oklch(58.2% 0.174 256) |
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 #2579DF | 4.30:1 | AA large text | Lc -74.7 | Content text, not long reading |
| Black text on #2579DF | 4.87:1 | AA | Lc 34.8 | Non-text elements, placeholder text |
| #2579DF text on white | 4.30:1 | AA large text | Lc 69.2 | Content text, not long reading |
| #2579DF text on black | 4.87:1 | AA | Lc -32.4 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBF9
oklch(93.6% 0.022 254.4)
-
Step 200
200
#C7DBF6
oklch(88.5% 0.043 255.9)
-
Step 300
300
#A0C3F3
oklch(80.9% 0.078 256.4)
-
Step 400
400
#6AA3ED
oklch(70.7% 0.125 255.5)
-
Step 500
500
#4089E8
oklch(63.1% 0.161 256.2)
-
Step 600
600 (this color)
#2579DF
oklch(58.2% 0.174 256)
-
Step 700
700
#0A5EBA
oklch(49.2% 0.162 256)
-
Step 800
800
#0F4D96
oklch(42.7% 0.134 256.1)
-
Step 900
900
#164178
oklch(37.8% 0.105 256.3)
-
Step 950
950
#0E2646
oklch(26.9% 0.067 256.5)
#2579DF 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) | #4183E3 | 0.036 |
| Deuteranopia (no green cones) | #0A72DD | 0.023 |
| Tritanopia (no blue cones) | #0092A1 | 0.133 |
| Achromatopsia (no color) | #7A7A7A | 0.174 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2579DF
#2579DF
oklch(58.2% 0.174 256)
- #A46F00
#A46F00
oklch(58.2% 0.122 75.8)
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 #2579DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean Blue #056EEE ΔE 0.041
- Royal Blue #4169E1 ΔE 0.042
- Clear Blue #247AFD ΔE 0.045
- Windows Blue #3778BF ΔE 0.049
- Water Blue #0E87CC ΔE 0.052
- Dark Sky Blue #448EE4 ΔE 0.064
- Neon Blue #4361EE ΔE 0.065
- Bright Blue #0165FC ΔE 0.070
Use #2579DF 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.