#255ECF
Closest named color: Warm Blue (#4B57DB). oklch(51.4% 0.185 262.1), rgb(37, 94, 207).
Aa
White text reads best on this color (5.86:1).
About this color
#255ECF is a medium-dark, vivid blue. In OKLCH its lightness is 51%, its chroma 0.185 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Warm Blue (#4B57DB), ΔE 0.043 away. White text reads best on it, at 5.86:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | vivid (0.185) |
| Temperature | cool |
| Nearest name | Warm Blue (#4B57DB) |
| Black text | 3.58:1 |
| White text | 5.86:1 |
Values
| HEX | #255ECF |
| RGB | rgb(37, 94, 207) |
| HSL | hsl(220, 70%, 48%) |
| OKLCH | oklch(51.4% 0.185 262.1) |
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 #255ECF | 5.86:1 | AA | Lc -84.0 | Fine for body text |
| Black text on #255ECF | 3.58:1 | AA large text | Lc 25.3 | Dividers and decoration only |
| #255ECF text on white | 5.86:1 | AA | Lc 78.7 | Fine for body text |
| #255ECF text on black | 3.58:1 | AA large text | Lc -23.1 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E1EAFC
oklch(93.6% 0.026 264.4)
-
Step 200
200
#C7DAFB
oklch(88.5% 0.05 261.5)
-
Step 300
300
#A1C1FB
oklch(80.8% 0.09 262.1)
-
Step 400
400
#6E9FF9
oklch(70.7% 0.143 261.7)
-
Step 500
500
#4883F6
oklch(63% 0.183 262.1)
-
Step 600
600
#2B69E5
oklch(55.5% 0.199 262.1)
-
Step 700
700 (this color)
#255ECF
oklch(51.4% 0.185 262.1)
-
Step 800
800
#1B48A1
oklch(42.7% 0.153 262)
-
Step 900
900
#1B3D80
oklch(37.6% 0.12 262.1)
-
Step 950
950
#11254B
oklch(27.1% 0.075 261.8)
#255ECF 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) | #006DD3 | 0.038 |
| Deuteranopia (no green cones) | #005DCD | 0.016 |
| Tritanopia (no blue cones) | #007A8D | 0.143 |
| Achromatopsia (no color) | #656565 | 0.185 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #255ECF
#255ECF
oklch(51.4% 0.185 262.1)
- #856000
#856000
oklch(51.4% 0.106 82.2)
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 #255ECF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Warm Blue #4B57DB ΔE 0.043
- Azul #1D5DEC ΔE 0.045
- Royal Blue #4169E1 ΔE 0.049
- Neon Blue #4361EE ΔE 0.057
- Mid Blue #276AB3 ΔE 0.057
- Cerulean Blue #056EEE ΔE 0.059
- Blue Blue #2242C7 ΔE 0.067
- Iris #6258C4 ΔE 0.070
Use #255ECF 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.