#1F77B1
Closest named color: Nice Blue (#107AB0). oklch(54.8% 0.12 243.3), rgb(31, 119, 177).
Aa
White text reads best on this color (4.84:1).
About this color
#1F77B1 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.120 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.010 away. White text reads best on it, at 4.84:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.33:1 |
| White text | 4.84:1 |
Values
| HEX | #1F77B1 |
| RGB | rgb(31, 119, 177) |
| HSL | hsl(204, 70%, 41%) |
| OKLCH | oklch(54.8% 0.12 243.3) |
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 #1F77B1 | 4.84:1 | AA | Lc -78.6 | Fine for body text |
| Black text on #1F77B1 | 4.33:1 | AA large text | Lc 30.9 | Non-text elements, placeholder text |
| #1F77B1 text on white | 4.84:1 | AA | Lc 73.2 | Content text, not long reading |
| #1F77B1 text on black | 4.33:1 | AA large text | Lc -28.5 | 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 600.
-
Step 50
50
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C9DCEC
oklch(88.5% 0.03 243.4)
-
Step 300
300
#A3C5E1
oklch(80.8% 0.054 243.3)
-
Step 400
400
#70A7D3
oklch(70.7% 0.087 243.6)
-
Step 500
500
#4790C7
oklch(63% 0.111 243.7)
-
Step 600
600 (this color)
#1F77B1
oklch(54.8% 0.12 243.3)
-
Step 700
700
#13669B
oklch(49.1% 0.112 243.6)
-
Step 800
800
#15537D
oklch(42.6% 0.092 243.6)
-
Step 900
900
#1A4565
oklch(37.7% 0.072 244.1)
-
Step 950
950
#10293B
oklch(27.1% 0.046 242.4)
#1F77B1 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) | #5C79B3 | 0.054 |
| Deuteranopia (no green cones) | #476CB0 | 0.040 |
| Tritanopia (no blue cones) | #00858C | 0.082 |
| Achromatopsia (no color) | #717171 | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F77B1
#1F77B1
oklch(54.8% 0.12 243.3)
- #A15F0D
#A15F0D
oklch(54.8% 0.12 63.4)
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 #1F77B1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.010
- Flat Blue #3C73A8 ΔE 0.022
- Windows Blue #3778BF ΔE 0.028
- Muted Blue #3B719F ΔE 0.032
- Mid Blue #276AB3 ΔE 0.038
- Ocean Blue #03719C ΔE 0.038
- French Blue #436BAD ΔE 0.039
- Dull Blue #49759C ΔE 0.042
Use #1F77B1 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.