Nearest-color comparison

Royal Blue vs Slate Blue

Royal Blue and Slate Blue are different blue colors with HEX values #4169E1 and #6A5ACD. According to Colors Encyclopedia, their RGB distance is 48, their contrast ratio is 1.1:1, and the comparison helps choose between tone, temperature, and accessibility behavior.

Royal Blue and Slate Blue are visually related colors. Royal Blue is the lighter option. They share similar temperature behavior. Their mutual contrast is 1.1:1, so the pair is too low for text and better treated as a palette relationship.

Differences Use cases Accessibility JSON

Royal Blue#4169E1

Slate Blue#6A5ACD

Quick Difference Summary

The main measurable differences between Royal Blue and Slate Blue across RGB distance, luminance, hue, saturation, and contrast.

RGB distance48

Pair contrast1.1:1

Luminance delta0.0188

Hue delta23 deg

Lighter colorRoyal Blue

More saturatedRoyal Blue

Side-by-Side Color Profiles

blue color

Royal Blue

Royal Blue is #4169E1, a cool blue color with vibrant character. Compared with Slate Blue, it is lighter and more saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.

HEX#4169E1 RGB65, 105, 225 HSL225, 73, 57 CMYK71, 53, 0, 12 Luminance0.1666 Best textwhite text

Color page WCAG HEX atlas

blue color

Slate Blue

Slate Blue is #6A5ACD, a cool blue color with balanced character. Compared with Royal Blue, it is darker and less saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.

HEX#6A5ACD RGB106, 90, 205 HSL248, 53, 58 CMYK48, 56, 0, 20 Luminance0.1478 Best textwhite text

Color page WCAG HEX atlas

When to Use Royal Blue or Slate Blue

Choose Royal BlueRoyal Blue is better when the design needs vibrant blue character, cool temperature, and the specific HEX value #4169E1.

Choose Slate BlueSlate Blue is better when the design needs balanced blue character, cool temperature, and the specific HEX value #6A5ACD.

Use togetherUse these colors together as related palette neighbors, subtle material differences, or tonal alternatives rather than readable foreground/background pairs.

Technical Comparison Table

PropertyRoyal BlueSlate Blue

HEX#4169E1#6A5ACD

RGB65, 105, 225106, 90, 205

HSL225, 73, 57248, 53, 58

CMYK71, 53, 0, 1248, 56, 0, 20

FamilyBlueBlue

TemperatureCoolCool

ToneVibrantBalanced

Luminance0.16660.1478

Black contrast4.33:13.96:1

White contrast4.85:15.31:1

Shared tonesNone

Accessibility and Contrast

Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.

Royal Bluewhite text - 4.85:1

Slate Bluewhite text - 5.31:1

Related Palette Strip

A compact visual strip showing the two compared colors with nearby harmony and variant context.

Royal Blue#4169E1

Slate Blue#6A5ACD

#91A8EE#91A8EE

#AAA1E2#AAA1E2

#E1B941#E1B941

#BECD5B#BECD5B

colorsBoth named color records with HEX, RGB, HSL, CMYK, luminance, WCAG, and links

differencesRGB distance, HSL deltas, luminance delta, contrast, and shared attributes

accessibilityPair contrast and safer text choices for each color

useCasesWhen to choose each color and when to use them together

relatedApiMachine-readable comparison and color endpoints

Structured sections

Colors

[
  {
    "slug": "royal-blue",
    "name": "Royal Blue",
    "hex": "#4169E1",
    "rgb": [
      65,
      105,
      225
    ],
    "hsl": [
      225,
      73,
      57
    ],
    "cmyk": [
      71,
      53,
      0,
      12
    ],
    "family": "blue",
    "temperature": "cool",
    "tone": [
      "vibrant"
    ],
    "luminance": 0.1666,
    "contrast": {
      "black": 4.33,
      "white": 4.85
    },
    "wcag": {
      "AA": [
        "#FFFFFF"
      ],
      "AAA": []
    },
    "bestText": {
      "text": "#FFFFFF",
      "label": "white text",
      "ratio": 4.85
    },
    "description": "Royal Blue is #4169E1, a cool blue color with vibrant character. Compared with Slate Blue, it is lighter and more saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.",
    "url": "https://www.colorsencyclopedia.com/colors/royal-blue/",
    "apiUrl": "https://www.colorsencyclopedia.com/api/colors/royal-blue.json"
  },
  {
    "slug": "slate-blue",
    "name": "Slate Blue",
    "hex": "#6A5ACD",
    "rgb": [
      106,
      90,
      205
    ],
    "hsl": [
      248,
      53,
      58
    ],
    "cmyk": [
      48,
      56,
      0,
      20
    ],
    "family": "blue",
    "temperature": "cool",
    "tone": [
      "balanced"
    ],
    "luminance": 0.1478,
    "contrast": {
      "black": 3.96,
      "white": 5.31
    },
    "wcag": {
      "AA": [
        "#FFFFFF",
        "#F5F5F5"
      ],
      "AAA": []
    },
    "bestText": {
      "text": "#FFFFFF",
      "label": "white text",
      "ratio": 5.31
    },
    "description": "Slate Blue is #6A5ACD, a cool blue color with balanced character. Compared with Royal Blue, it is darker and less saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.",
    "url": "https://www.colorsencyclopedia.com/colors/slate-blue/",
    "apiUrl": "https://www.colorsencyclopedia.com/api/colors/slate-blue.json"
  }
]

Differences

{
  "rgbDistance": 48,
  "contrastRatio": 1.1,
  "hslDelta": {
    "hue": 23,
    "saturation": 20,
    "lightness": 1
  },
  "luminanceDelta": 0.0188,
  "sameFamily": true,
  "sameTemperature": true,
  "sharedTones": [],
  "lighterColor": "Royal Blue",
  "moreSaturatedColor": "Royal Blue"
}

Accessibility

{
  "pairContrastRatio": 1.1,
  "textRecommendation": "Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.",
  "safeText": [
    {
      "color": "Royal Blue",
      "background": "#4169E1",
      "foreground": "#FFFFFF",
      "label": "white text",
      "ratio": 4.85
    },
    {
      "color": "Slate Blue",
      "background": "#6A5ACD",
      "foreground": "#FFFFFF",
      "label": "white text",
      "ratio": 5.31
    }
  ]
}

Use cases

{
  "chooseFirstWhen": "Royal Blue is better when the design needs vibrant blue character, cool temperature, and the specific HEX value #4169E1.",
  "chooseSecondWhen": "Slate Blue is better when the design needs balanced blue character, cool temperature, and the specific HEX value #6A5ACD.",
  "useTogetherWhen": "Use these colors together as related palette neighbors, subtle material differences, or tonal alternatives rather than readable foreground/background pairs."
}

Related API

[
  "https://www.colorsencyclopedia.com/api/compare/royal-blue-vs-slate-blue.json",
  "https://www.colorsencyclopedia.com/api/colors/royal-blue.json",
  "https://www.colorsencyclopedia.com/api/colors/slate-blue.json"
]

Full JSON dataset

{
  "datasetVersion": "1.0.0",
  "slug": "royal-blue-vs-slate-blue",
  "type": "nearest",
  "name": "Royal Blue vs Slate Blue",
  "verdict": "Royal Blue and Slate Blue are visually related colors. Royal Blue is the lighter option. They share similar temperature behavior. Their mutual contrast is 1.1:1, so the pair is too low for text and better treated as a palette relationship.",
  "summary": "Royal Blue and Slate Blue are different blue colors with HEX values #4169E1 and #6A5ACD. According to Colors Encyclopedia, their RGB distance is 48, their contrast ratio is 1.1:1, and the comparison helps choose between tone, temperature, and accessibility behavior.",
  "rgbDistance": 48,
  "contrastRatio": 1.1,
  "colors": [
    {
      "slug": "royal-blue",
      "name": "Royal Blue",
      "hex": "#4169E1",
      "rgb": [
        65,
        105,
        225
      ],
      "hsl": [
        225,
        73,
        57
      ],
      "cmyk": [
        71,
        53,
        0,
        12
      ],
      "family": "blue",
      "temperature": "cool",
      "tone": [
        "vibrant"
      ],
      "luminance": 0.1666,
      "contrast": {
        "black": 4.33,
        "white": 4.85
      },
      "wcag": {
        "AA": [
          "#FFFFFF"
        ],
        "AAA": []
      },
      "bestText": {
        "text": "#FFFFFF",
        "label": "white text",
        "ratio": 4.85
      },
      "description": "Royal Blue is #4169E1, a cool blue color with vibrant character. Compared with Slate Blue, it is lighter and more saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.",
      "url": "https://www.colorsencyclopedia.com/colors/royal-blue/",
      "apiUrl": "https://www.colorsencyclopedia.com/api/colors/royal-blue.json"
    },
    {
      "slug": "slate-blue",
      "name": "Slate Blue",
      "hex": "#6A5ACD",
      "rgb": [
        106,
        90,
        205
      ],
      "hsl": [
        248,
        53,
        58
      ],
      "cmyk": [
        48,
        56,
        0,
        20
      ],
      "family": "blue",
      "temperature": "cool",
      "tone": [
        "balanced"
      ],
      "luminance": 0.1478,
      "contrast": {
        "black": 3.96,
        "white": 5.31
      },
      "wcag": {
        "AA": [
          "#FFFFFF",
          "#F5F5F5"
        ],
        "AAA": []
      },
      "bestText": {
        "text": "#FFFFFF",
        "label": "white text",
        "ratio": 5.31
      },
      "description": "Slate Blue is #6A5ACD, a cool blue color with balanced character. Compared with Royal Blue, it is darker and less saturated. Use it for web design, css color systems, and ui prototyping, with white text as the safer foreground option.",
      "url": "https://www.colorsencyclopedia.com/colors/slate-blue/",
      "apiUrl": "https://www.colorsencyclopedia.com/api/colors/slate-blue.json"
    }
  ],
  "differences": {
    "rgbDistance": 48,
    "contrastRatio": 1.1,
    "hslDelta": {
      "hue": 23,
      "saturation": 20,
      "lightness": 1
    },
    "luminanceDelta": 0.0188,
    "sameFamily": true,
    "sameTemperature": true,
    "sharedTones": [],
    "lighterColor": "Royal Blue",
    "moreSaturatedColor": "Royal Blue"
  },
  "accessibility": {
    "pairContrastRatio": 1.1,
    "textRecommendation": "Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.",
    "safeText": [
      {
        "color": "Royal Blue",
        "background": "#4169E1",
        "foreground": "#FFFFFF",
        "label": "white text",
        "ratio": 4.85
      },
      {
        "color": "Slate Blue",
        "background": "#6A5ACD",
        "foreground": "#FFFFFF",
        "label": "white text",
        "ratio": 5.31
      }
    ]
  },
  "useCases": {
    "chooseFirstWhen": "Royal Blue is better when the design needs vibrant blue character, cool temperature, and the specific HEX value #4169E1.",
    "chooseSecondWhen": "Slate Blue is better when the design needs balanced blue character, cool temperature, and the specific HEX value #6A5ACD.",
    "useTogetherWhen": "Use these colors together as related palette neighbors, subtle material differences, or tonal alternatives rather than readable foreground/background pairs."
  },
  "relatedApi": [
    "https://www.colorsencyclopedia.com/api/compare/royal-blue-vs-slate-blue.json",
    "https://www.colorsencyclopedia.com/api/colors/royal-blue.json",
    "https://www.colorsencyclopedia.com/api/colors/slate-blue.json"
  ],
  "url": "https://www.colorsencyclopedia.com/compare/royal-blue-vs-slate-blue/",
  "apiUrl": "https://www.colorsencyclopedia.com/api/compare/royal-blue-vs-slate-blue.json"
}