#637EFE

Closest named color: Cornflower (#6A79F7). oklch(63.8% 0.192 271.1), rgb(99, 126, 254).

Aa

Black text reads best on this color (5.94:1).

About this color

#637EFE is a medium-light, vivid blue. In OKLCH its lightness is 64%, its chroma 0.192 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower (#6A79F7), ΔE 0.016 away. Black text reads best on it, at 5.94:1.

Hue familyBlues
Lightnessmedium-light (64%)
Chromavivid (0.192)
Temperaturecool
Nearest nameCornflower (#6A79F7)
Black text5.94:1
White text3.53:1

Values

HEX#637EFE
RGBrgb(99, 126, 254)
HSLhsl(230, 99%, 69%)
OKLCHoklch(63.8% 0.192 271.1)

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.

PairWCAG 2ResultAPCAAPCA guidance
White text on #637EFE 3.53:1 AA large text Lc -68.0 Content text, not long reading
Black text on #637EFE 5.94:1 AA Lc 41.5 Non-text elements, placeholder text
#637EFE text on white 3.53:1 AA large text Lc 62.6 Content text, not long reading
#637EFE text on black 5.94:1 AA Lc -39.1 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 500.

  1. Step 50

    50

    #F2F5FE

    oklch(97% 0.012 271.3)

  2. Step 100

    100

    #E3E9FD

    oklch(93.5% 0.028 272.5)

  3. Step 200

    200

    #CCD8FD

    oklch(88.5% 0.053 271.1)

  4. Step 300

    300

    #AABEFE

    oklch(81% 0.094 270.8)

  5. Step 400

    400

    #7F99FD

    oklch(70.7% 0.149 271.2)

  6. Step 500

    500 (this color)

    #637EFE

    oklch(63.8% 0.192 271.1)

  7. Step 600

    600

    #4B61EB

    oklch(55.7% 0.208 271.1)

  8. Step 700

    700

    #3D4FCC

    oklch(49.2% 0.193 271.1)

  9. Step 800

    800

    #3241A5

    oklch(42.7% 0.161 271.3)

  10. Step 900

    900

    #2B3983

    oklch(37.8% 0.125 271.1)

  11. Step 950

    950

    #19224D

    oklch(27.1% 0.08 271.2)

Export this scale for Tailwind in the Tailwind colors tool

#637EFE 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.

VisionSeen asShift (ΔE)
Protanopia (no red cones)#358FFF0.052
Deuteranopia (no green cones)#0082FB0.060
Tritanopia (no blue cones)#009CB20.164
Achromatopsia (no color)#8888880.192

Harmonies

Hue rotations in OKLCH that keep this color's lightness and chroma.

Complementary

The opposite hue (180°).

  • #637EFE

    #637EFE

    oklch(63.8% 0.192 271.1)

  • #A98700

    #A98700

    oklch(63.7% 0.13 90.9)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #637EFE

    #637EFE

    oklch(63.8% 0.192 271.1)

  • #0094DD

    #0094DD

    oklch(63.8% 0.15 241.4)

  • #A168EB

    #A168EB

    oklch(63.7% 0.192 301.2)

Open the analogous palette in the generator

Split complementary

The two hues beside the complement (150° and 210°).

  • #637EFE

    #637EFE

    oklch(63.8% 0.192 271.1)

  • #CA7300

    #CA7300

    oklch(63.9% 0.148 61.4)

  • #7E9900

    #7E9900

    oklch(63.9% 0.154 121.4)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #637EFE

    #637EFE

    oklch(63.8% 0.192 271.1)

  • #E9513B

    #E9513B

    oklch(63.9% 0.192 31.1)

  • #00A751

    #00A751

    oklch(63.7% 0.171 151.1)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #637EFE

    #637EFE

    oklch(63.8% 0.192 271.1)

  • #E24C85

    #E24C85

    oklch(63.8% 0.191 0.8)

  • #A98700

    #A98700

    oklch(63.7% 0.13 90.9)

  • #00A290

    #00A290

    oklch(63.9% 0.115 181.3)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #637EFE, closest first.

No curated palette has a color within ΔE 0.04 of #637EFE.

Similar named colors

The eight closest entries in our named color list, with their ΔE distance.

Use #637EFE 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.