Nearest-color comparison
Sapphire #0F52BA vs Signal Blue #0057B8: RGB distance 15.9 and contrast 1.04:1. Compare hue, luminance, saturation, WCAG and practical use.
Sapphire and Signal Blue are very close, with an RGB distance of 15.9. Signal Blue is lighter by 0.006, and Signal Blue is more saturated by 15 percentage points. Their mutual contrast is 1.04:1. The pair is too close for a readable foreground/background combination and works better as neighboring palette colors.
The main measurable differences between Sapphire and Signal Blue across RGB distance, luminance, hue, saturation, and contrast.
blue color
Sapphire is #0F52BA, a cool blue with hue 216°, saturation 85% and luminance 0.0968. Beside Signal Blue, it is darker and less saturated. Of the two standard text choices, white text gives the higher contrast at 7.15:1.
blue color
Signal Blue is #0057B8, a cool blue with hue 212°, saturation 100% and luminance 0.1028. Beside Sapphire, it is lighter and more saturated. Of the two standard text choices, white text gives the higher contrast at 6.87:1.
Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.
Downloadable color comparison infographic
Save a high-resolution comparison infographic with both HEX colors, visual distance, mutual contrast, and accessibility guidance.
A compact visual strip showing the two compared colors with nearby harmony and variant context.
Machine-readable data
Structured comparison data for Sapphire and Signal Blue, including color systems, RGB distance, HSL deltas, contrast, accessibility guidance, use cases, and API links.
Colors Encyclopedia
colorsBoth named color records with HEX, RGB, HSL, CMYK, luminance, WCAG, and linksdifferencesRGB distance, HSL deltas, luminance delta, contrast, and shared attributesaccessibilityPair contrast and safer text choices for each coloruseCasesWhen to choose each color and when to use them togetherrelatedApiMachine-readable comparison and color endpoints[
{
"slug": "sapphire",
"name": "Sapphire",
"hex": "#0F52BA",
"rgb": [
15,
82,
186
],
"hsl": [
216,
85,
39
],
"cmyk": [
92,
56,
0,
27
],
"family": "blue",
"temperature": "cool",
"tone": [
"vibrant",
"jewel-tone"
],
"luminance": 0.0968,
"contrast": {
"black": 2.94,
"white": 7.15
},
"wcag": {
"AA": [
"#FFFFFF",
"#F5F5F5"
],
"AAA": [
"#FFFFFF"
]
},
"bestText": {
"text": "#FFFFFF",
"label": "white text",
"ratio": 7.15
},
"description": "Sapphire is #0F52BA, a cool blue color with vibrant and jewel tone character. Compared with Signal Blue, it is darker and less saturated. Use it for interfaces, brand systems, and technical design, with white text as the safer foreground option.",
"url": "https://www.colorsencyclopedia.com/colors/sapphire/",
"apiUrl": "https://www.colorsencyclopedia.com/api/colors/sapphire.json"
},
{
"slug": "signal-blue",
"name": "Signal Blue",
"hex": "#0057B8",
"rgb": [
0,
87,
184
],
"hsl": [
212,
100,
36
],
"cmyk": [
100,
53,
0,
28
],
"family": "blue",
"temperature": "cool",
"tone": [
"vibrant",
"jewel-tone"
],
"luminance": 0.1028,
"contrast": {
"black": 3.06,
"white": 6.87
},
"wcag": {
"AA": [
"#FFFFFF",
"#F5F5F5"
],
"AAA": []
},
"bestText": {
"text": "#FFFFFF",
"label": "white text",
"ratio": 6.87
},
"description": "Signal Blue is #0057B8, a cool blue color with vibrant and jewel tone character. Compared with Sapphire, it is lighter and more saturated. Use it for industrial design, safety systems, and hardware palettes, with white text as the safer foreground option.",
"url": "https://www.colorsencyclopedia.com/colors/signal-blue/",
"apiUrl": "https://www.colorsencyclopedia.com/api/colors/signal-blue.json"
}
]{
"rgbDistance": 15.9,
"contrastRatio": 1.04,
"hslDelta": {
"hue": 4,
"saturation": 15,
"lightness": 3
},
"luminanceDelta": 0.006,
"sameFamily": true,
"sameTemperature": true,
"sharedTones": [
"vibrant",
"jewel-tone"
],
"lighterColor": "Signal Blue",
"moreSaturatedColor": "Signal Blue"
}{
"pairContrastRatio": 1.04,
"textRecommendation": "Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.",
"safeText": [
{
"color": "Sapphire",
"background": "#0F52BA",
"foreground": "#FFFFFF",
"label": "white text",
"ratio": 7.15
},
{
"color": "Signal Blue",
"background": "#0057B8",
"foreground": "#FFFFFF",
"label": "white text",
"ratio": 6.87
}
]
}{
"chooseFirstWhen": "Sapphire is better when the design needs vibrant and jewel tone blue character, cool temperature, and the specific HEX value #0F52BA.",
"chooseSecondWhen": "Signal Blue is better when the design needs vibrant and jewel tone blue character, cool temperature, and the specific HEX value #0057B8.",
"useTogetherWhen": "Use these colors together as related palette neighbors, subtle material differences, or tonal alternatives rather than readable foreground/background pairs."
}[
"https://www.colorsencyclopedia.com/api/compare/sapphire-vs-signal-blue.json",
"https://www.colorsencyclopedia.com/api/colors/sapphire.json",
"https://www.colorsencyclopedia.com/api/colors/signal-blue.json"
]{
"datasetVersion": "1.0.0",
"slug": "sapphire-vs-signal-blue",
"type": "nearest",
"name": "Sapphire vs Signal Blue",
"verdict": "Sapphire and Signal Blue are very close colors. Signal Blue is the lighter option. They share similar temperature behavior. Their mutual contrast is 1.04:1, so the pair is too low for text and better treated as a palette relationship.",
"summary": "Sapphire and Signal Blue are different blue colors with HEX values #0F52BA and #0057B8. According to Colors Encyclopedia, their RGB distance is 15.9, their contrast ratio is 1.04:1, and the comparison helps choose between tone, temperature, and accessibility behavior.",
"rgbDistance": 15.9,
"contrastRatio": 1.04,
"colors": [
{
"slug": "sapphire",
"name": "Sapphire",
"hex": "#0F52BA",
"rgb": [
15,
82,
186
],
"hsl": [
216,
85,
39
],
"cmyk": [
92,
56,
0,
27
],
"family": "blue",
"temperature": "cool",
"tone": [
"vibrant",
"jewel-tone"
],
"luminance": 0.0968,
"contrast": {
"black": 2.94,
"white": 7.15
},
"wcag": {
"AA": [
"#FFFFFF",
"#F5F5F5"
],
"AAA": [
"#FFFFFF"
]
},
"bestText": {
"text": "#FFFFFF",
"label": "white text",
"ratio": 7.15
},
"description": "Sapphire is #0F52BA, a cool blue color with vibrant and jewel tone character. Compared with Signal Blue, it is darker and less saturated. Use it for interfaces, brand systems, and technical design, with white text as the safer foreground option.",
"url": "https://www.colorsencyclopedia.com/colors/sapphire/",
"apiUrl": "https://www.colorsencyclopedia.com/api/colors/sapphire.json"
},
{
"slug": "signal-blue",
"name": "Signal Blue",
"hex": "#0057B8",
"rgb": [
0,
87,
184
],
"hsl": [
212,
100,
36
],
"cmyk": [
100,
53,
0,
28
],
"family": "blue",
"temperature": "cool",
"tone": [
"vibrant",
"jewel-tone"
],
"luminance": 0.1028,
"contrast": {
"black": 3.06,
"white": 6.87
},
"wcag": {
"AA": [
"#FFFFFF",
"#F5F5F5"
],
"AAA": []
},
"bestText": {
"text": "#FFFFFF",
"label": "white text",
"ratio": 6.87
},
"description": "Signal Blue is #0057B8, a cool blue color with vibrant and jewel tone character. Compared with Sapphire, it is lighter and more saturated. Use it for industrial design, safety systems, and hardware palettes, with white text as the safer foreground option.",
"url": "https://www.colorsencyclopedia.com/colors/signal-blue/",
"apiUrl": "https://www.colorsencyclopedia.com/api/colors/signal-blue.json"
}
],
"differences": {
"rgbDistance": 15.9,
"contrastRatio": 1.04,
"hslDelta": {
"hue": 4,
"saturation": 15,
"lightness": 3
},
"luminanceDelta": 0.006,
"sameFamily": true,
"sameTemperature": true,
"sharedTones": [
"vibrant",
"jewel-tone"
],
"lighterColor": "Signal Blue",
"moreSaturatedColor": "Signal Blue"
},
"accessibility": {
"pairContrastRatio": 1.04,
"textRecommendation": "Do not use this pair for text; use it for neighboring palette colors, decoration, or low-emphasis surfaces.",
"safeText": [
{
"color": "Sapphire",
"background": "#0F52BA",
"foreground": "#FFFFFF",
"label": "white text",
"ratio": 7.15
},
{
"color": "Signal Blue",
"background": "#0057B8",
"foreground": "#FFFFFF",
"label": "white text",
"ratio": 6.87
}
]
},
"useCases": {
"chooseFirstWhen": "Sapphire is better when the design needs vibrant and jewel tone blue character, cool temperature, and the specific HEX value #0F52BA.",
"chooseSecondWhen": "Signal Blue is better when the design needs vibrant and jewel tone blue character, cool temperature, and the specific HEX value #0057B8.",
"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/sapphire-vs-signal-blue.json",
"https://www.colorsencyclopedia.com/api/colors/sapphire.json",
"https://www.colorsencyclopedia.com/api/colors/signal-blue.json"
],
"url": "https://www.colorsencyclopedia.com/compare/sapphire-vs-signal-blue/",
"apiUrl": "https://www.colorsencyclopedia.com/api/compare/sapphire-vs-signal-blue.json"
}