Skip to main content

Red

#FF0000·red family·WCAG AA

Tints & Shades

50

100

200

300

400

500

600

700

800

900

Scale from white (50) through Red (500) to black (900), interpolated in Lab color space.

Color Values

HEX
#FF0000
RGB
rgb(255, 0, 0)
HSL
hsl(0, 100%, 50%)
OKLCH
oklch(0.628 0.258 29)
CMYK
cmyk(0%, 100%, 100%, 0%)
Luminance:0.2126
CSS var:--color-red
Tailwind:bg-[#FF0000]

Accessibility

Score: 39/100

On White (#FFF)

4:1

AA Large

On Black (#000)

5.25:1

AA

On Light Gray (#F5F5F5)

3.67:1

AA Large

Best text color on this background:

black5.25:1
Open in Contrast Checker →

Design Applications

Background

background-color: #FF0000

Text Color

color: #FF0000

bg-[#FF0000] text-[#000000]

Accent border card component

border-left: 4px solid #FF0000

Color Meaning & Psychology

Pure red is the highest-chroma, most emotionally intense tone in the spectrum. It triggers the fastest autonomic nervous system response of any color — used by every culture as the color of blood, fire, and immediate danger. In modern branding, pure red belongs to stop signs, Coca-Cola, Netflix, and YouTube — brands designed to command instant, global recognition.

Industry Usage

Common contexts and industries where Red is applied in professional design.

  • Emergency alerts and warning systems
  • Food and beverage brands (appetite stimulation)
  • Sports teams and athletic wear
  • Calls-to-action and "Buy Now" buttons
  • Pharmaceutical packaging for urgent medications
  • Entertainment and gaming brands
  • Automotive brands emphasizing power and performance
  • Retail sale and clearance signage

Accessibility Considerations

Normal Text

Fails AA

4.5:1 minimum required

Large Text

Passes AA Large

3:1 minimum required

UI Components

Meets 1.4.11

3:1 for non-text UI

Red is a light color. Use black (#000000) text on top of it for maximum readability (5.25:1). Avoid white text on this background.

CSS & Code Examples

Background

background-color: #FF0000;

Text

color: #FF0000;

Border

border: 2px solid #FF0000;

Box Shadow

box-shadow: 0 4px 20px #FF000040;

Gradient

background: linear-gradient(135deg, #FF0000, #ff5a36);

Tailwind-style

--color-red: #FF0000;

Tailwind CSS Utilities

Use arbitrary value syntax in Tailwind CSS to apply Red without a custom config.

Background

bg-[#FF0000]

Text

text-[#FF0000]

Border

border-[#FF0000]

Ring

ring-[#FF0000]

Fill

fill-[#FF0000]

From (gradient)

from-[#FF0000]

Via (gradient)

via-[#FF0000]

To (gradient)

to-[#FF0000]

Design Tokens

Ready-to-use Red design token in CSS custom properties, SCSS, Tailwind v3/v4, and JSON formats.

CSS Custom Properties

:root {
  --color-red: #FF0000;
  --color-red-rgb: 255, 0, 0;
  --color-red-hsl: 0, 100%, 50%;
}

SCSS Variables

$color-red: #FF0000;
$color-red-rgb: 255, 0, 0;
$color-red-hsl: 0, 100%, 50%;

Tailwind v3 Config

// tailwind.config.js
module.exports = {
  theme: {
    extend: {
      colors: {
        'red': '#FF0000',
      },
    },
  },
};

Tailwind v4 (@theme)

/* tailwind.css */
@theme {
  --color-red: #FF0000;
}

JSON Design Token (W3C format)

{
  "red": {
    "value": "#FF0000",
    "type": "color",
    "description": "Red — #FF0000"
  }
}

What Does Red Mean? Color Psychology & Cultural Symbolism

At #FF0000, Red is a medium interpretation of the red family—toning down the alarm of pure red into urgency territory. The 50% lightness reading positions it between a shout and a statement: present, intentional, and emotionally active.

  • Across color psychology research, red consistently tests high for "energy" associations, making Red a reliable vehicle for urgency in cross-demographic audiences.
  • Brand designers draw on red-family tones to project excitement and urgency—values that Red communicates in a medium key.
  • At 100% saturation, Red reads as vivid—Pure saturated reds are physiologically stimulating, triggering faster heart rate and heightened alertness—among the most attention-commanding tones in human visual perception.
  • Red's medium lightness (50%) shifts its psychological register: a balanced mid-tone that embodies energy, passion, urgency, and power at its most direct.

The rule with Red is intent—when it appears, it should carry meaning. Urgency, passion, importance. Never filler.

How to Use Red in Design: Applications, Pairings & Best Practices

Red rewards restraint in design. Used at full-surface scale it creates urgency that borders on stress; deployed as a targeted accent—a button, a badge, a border—it creates the focused emphasis that drives conversions.

  • Avoid: financial dashboards (loss association), environmental brands (conflicts with green identity), and medical UIs where red exclusively signals critical alerts.
  • Color harmonies: Red's complementary color creates a high-energy split ideal for promotional design; its analogous palette (±30° hue) builds cohesive, monochromatic sophistication.
  • Proportional use: Red's vivid saturation (100%) means small applications—accents, highlights, icons—deliver maximum impact without visual fatigue. Reserve large-scale use for intentional brand moments.
  • Red creates strong legibility with black text overlays (5.3:1 contrast ratio), making it a reliable background or surface color in design systems
  • Typography: Red as text requires a dark background; its 50% lightness means it provides 4.0:1 contrast on white, not meeting WCAG AA.

The rule with Red is intent—when it appears, it should carry meaning. Urgency, passion, importance. Never filler.

Red Accessibility: WCAG Contrast Ratios, Color Blindness & Inclusive Design

Red (#FF0000) reaches 5.25:1 contrast with black text—meeting WCAG 2.1 AA minimum of 4.5:1 for normal text and 3:1 for large text. It clears standard production accessibility requirements. Relative luminance: 21.3%.

  • As text on white (#FFFFFF): 4.00:1 — AA (large text only)
  • As text on black (#000000): 5.25:1 — AA ✓
  • Best text color on Red background: Black (#000000) at 5.25:1
  • WCAG 2.1 luminance: 21.3% — mid-range luminance—it sits in the transition zone where both dark and light text approaches require testing against the 4.5:1 WCAG threshold
  • Red qualifies for normal body text and all larger sizes (AA).
  • Color blindness consideration: protanopia and deuteranopia (red-green color blindness, ~8% of males) may affect how red-family colors are distinguished from greens and browns. For critical UI states, supplement color alone with shape, label, or pattern cues.

For production use, test Red against your specific background colors rather than assuming #FFFFFF or #000000 performance translates. Surrounding colors alter perceived contrast.

Red in Industry: Branding, Design & Market Applications

Red (#FF0000) is most at home in industries where energy, passion, urgency, and power are key brand values. Its medium quality makes it particularly effective in Food & Beverage contexts, where the vivid saturation signals energy at exactly the right register.

  • Food & Beverage: Red stimulates appetite and accelerates purchase decisions. Fast food chains, hot sauce brands, and snack packaging use it deliberately because it increases caloric craving and speeds up decision-making at point of sale. (examples: Whole Foods, Trader Joe's, Blue Bottle Coffee) Avoid in fine dining or health-food contexts where a slower, more mindful experience is the goal.
  • Retail & E-commerce: The "red sale tag" is a globally conditioned retail convention. Red signals scarcity and urgency, making it the universal shorthand for clearance events, limited-time offers, and price callouts. (examples: Shopify merchant sites, ASOS, H&M) Overuse exhausts the urgency signal—reserve it for genuinely time-limited promotions.
  • Sports & Entertainment: Red communicates competition, athletic energy, and tribal passion. From team jerseys to arena signage, it energizes crowds and aligns with the visceral intensity sports brands want to project. (examples: Disney+, Hulu, Netflix) Works best paired with black or white for maximum contrast and visual impact.
  • Brand positioning: Red is best suited for brands projecting energy, passion, importance. Categories outside this positioning—financial dashboards (loss association)—tend to see weaker results.
  • Adjacent applications: Beyond primary industries, Red works effectively in call-to-action buttons, promotional banners, food packaging—contexts where energy serves a secondary but reinforcing role.

The industries where Red performs best are those where the audience expects energy. Build brand strategy around this alignment, not against it.

Frequently Asked Questions

What is the hex code for Red?
The hex code for Red is #FF0000. Its RGB values are rgb(255, 0, 0) and its HSL values are hsl(0, 100%, 50%).
What does Red mean in design?
Pure red is the highest-chroma, most emotionally intense tone in the spectrum. It triggers the fastest autonomic nervous system response of any color — used by every culture as the color of blood, fire, and immediate danger. In modern branding, pure red belongs to stop signs, Coca-Cola, Netflix, and YouTube — brands designed to command instant, global recognition.
Is Red WCAG accessible?
Red (#FF0000) passes WCAG AA-large on white with a 4:1 contrast ratio. Its overall accessibility score is 39/100.
What colors go well with Red?
Red pairs well with its complementary color Iron Gray (#595E5E). Analogous colors like Hot Pink and Burgundy also work harmoniously. Check the Color Harmonies section above for the full palette.
What is Red used for?
Red is commonly used for: Emergency alerts and warning systems; Food and beverage brands (appetite stimulation); Sports teams and athletic wear; Calls-to-action and "Buy Now" buttons; Pharmaceutical packaging for urgent medications.
What are the CSS and Tailwind values for Red?
In CSS, use `color: #FF0000` or `background-color: #FF0000`. The CSS custom property is `--color-red: #FF0000`. In Tailwind CSS, use the arbitrary value class `bg-[#FF0000]` for backgrounds or `text-[#FF0000]` for text.