#637797
Closest named color: Stormy Blue (#507B9C). oklch(56.6% 0.055 259.7), rgb(99, 119, 151).
Aa
Black text reads best on this color (4.61:1).
About this color
#637797 is a medium-dark, muted blue. In OKLCH its lightness is 57%, its chroma 0.055 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Stormy Blue (#507B9C), ΔE 0.024 away. Black text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | muted (0.055) |
| Temperature | cool |
| Nearest name | Stormy Blue (#507B9C) |
| Black text | 4.61:1 |
| White text | 4.54:1 |
Values
| HEX | #637797 |
| RGB | rgb(99, 119, 151) |
| HSL | hsl(217, 21%, 49%) |
| OKLCH | oklch(56.6% 0.055 259.7) |
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 #637797 | 4.54:1 | AA | Lc -77.0 | Fine for body text |
| Black text on #637797 | 4.61:1 | AA | Lc 32.5 | Non-text elements, placeholder text |
| #637797 text on white | 4.54:1 | AA | Lc 71.6 | Content text, not long reading |
| #637797 text on black | 4.61:1 | AA | Lc -30.1 | 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
#F4F5F8
oklch(97% 0.004 271.4)
-
Step 100
100
#E7EAEF
oklch(93.6% 0.007 260.7)
-
Step 200
200
#D4D9E2
oklch(88.4% 0.013 262.4)
-
Step 300
300
#B7C1D1
oklch(80.8% 0.025 259.8)
-
Step 400
400
#92A2BA
oklch(70.8% 0.04 258.4)
-
Step 500
500
#788AA9
oklch(63% 0.051 261.2)
-
Step 600
600 (this color)
#637797
oklch(56.6% 0.055 259.7)
-
Step 700
700
#50617E
oklch(49% 0.051 261)
-
Step 800
800
#415067
oklch(42.8% 0.043 258.8)
-
Step 900
900
#374253
oklch(37.6% 0.033 259)
-
Step 950
950
#202731
oklch(27% 0.021 257.3)
#637797 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) | #6C7998 | 0.014 |
| Deuteranopia (no green cones) | #667496 | 0.009 |
| Tritanopia (no blue cones) | #537E82 | 0.049 |
| Achromatopsia (no color) | #767676 | 0.055 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637797
#637797
oklch(56.6% 0.055 259.7)
- #877351
#877351
oklch(56.6% 0.055 80.5)
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 #637797, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Stormy Blue #507B9C ΔE 0.024
- Grey Blue #647D8E ΔE 0.026
- Metallic Blue #4F738E ΔE 0.032
- Dull Blue #49759C ΔE 0.033
- Cerulean #457B9D ΔE 0.034
- Slate Gray #708090 ΔE 0.037
- Battleship Grey #6B7C85 ΔE 0.037
- Battleship Gray #6C757D ΔE 0.040
Use #637797 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.