#1F7BBC
Closest named color: Windows Blue (#3778BF). oklch(56.3% 0.13 245.3), rgb(31, 123, 188).
Aa
Black text reads best on this color (4.61:1).
About this color
#1F7BBC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.130 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.017 away. Black text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.130) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.61:1 |
| White text | 4.54:1 |
Values
| HEX | #1F7BBC |
| RGB | rgb(31, 123, 188) |
| HSL | hsl(205, 72%, 43%) |
| OKLCH | oklch(56.3% 0.13 245.3) |
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 #1F7BBC | 4.54:1 | AA | Lc -76.6 | Fine for body text |
| Black text on #1F7BBC | 4.61:1 | AA | Lc 32.9 | Non-text elements, placeholder text |
| #1F7BBC text on white | 4.54:1 | AA | Lc 71.1 | Content text, not long reading |
| #1F7BBC text on black | 4.61:1 | AA | Lc -30.5 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C8DCEE
oklch(88.5% 0.033 245.3)
-
Step 300
300
#A2C5E4
oklch(80.8% 0.058 245.3)
-
Step 400
400
#6DA7D7
oklch(70.7% 0.093 244.6)
-
Step 500
500
#4390CD
oklch(63.2% 0.119 245.3)
-
Step 600
600 (this color)
#1F7BBC
oklch(56.3% 0.13 245.3)
-
Step 700
700
#0A65A0
oklch(49% 0.121 245.5)
-
Step 800
800
#105382
oklch(42.8% 0.1 245.4)
-
Step 900
900
#174568
oklch(37.7% 0.078 245.2)
-
Step 950
950
#0F293D
oklch(27.1% 0.049 244.3)
#1F7BBC 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) | #5C7EBF | 0.053 |
| Deuteranopia (no green cones) | #4670BB | 0.038 |
| Tritanopia (no blue cones) | #008B93 | 0.091 |
| Achromatopsia (no color) | #767676 | 0.130 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F7BBC
#1F7BBC
oklch(56.3% 0.13 245.3)
- #A76300
#A76300
oklch(56.3% 0.126 65)
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 #1F7BBC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.017
- Nice Blue #107AB0 ΔE 0.020
- Flat Blue #3C73A8 ΔE 0.036
- Water Blue #0E87CC ΔE 0.037
- Steel Blue #4682B4 ΔE 0.039
- Cool Blue #4984B8 ΔE 0.044
- Mid Blue #276AB3 ΔE 0.047
- French Blue #436BAD ΔE 0.048
Use #1F7BBC 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.