Recognised as Colour

#F21509

#F21509
Red
Dark
Nearest: Red

#F21509 is a red with RGB values 242, 21, 9 and HSL 3°, 93%, 49%. It is a dark colour, so black text on it reaches 4.9:1 contrast (AA for normal text). The nearest named colour is Red.

Colour values

#F21509#F21509

HEX#F21509

RGBrgb(242, 21, 9)

RGB (0–1)0.949, 0.0824, 0.0353

RGB percentages94.9%, 8.2%, 3.5%

HSLhsl(3.1, 92.8%, 49.2%)

HSV / HSBhsv(3.1, 96.3%, 94.9%)

CMYK0%, 91.3%, 96.3%, 5.1%≈naive device-independent conversion; real print needs an ICC profile

24-bit integer15,865,097

CSS custom property--colour: #F21509;

Brightness & contrast

Relative luminance0.19433WCAG 2.x, 0 is black and 1 is white

Perceived brightness133.3 of 255ITU-R BT.601 weighting

Light or darkDark

Best text colour on this backgroundBlackcontrast 4.89:1

Contrast with white4.3:1WCAG normal text: Fail

Contrast with black4.89:1WCAG normal text: AA

Greyscale equivalent#434343

Inverted#0DEAF6

Colour vision & accessibility

Normal vision Protanopia Deuteranopia Tritanopia

Protanopia#695C00no red cones; affects about 1% of men; ΔE 81.6 from the original

Deuteranopia#9C8A00no green cones; the most common form, about 1% of men; ΔE 80.8 from the original

Tritanopia#FF001Ano blue cones; rare, and affects men and women equally; ΔE 6.2 from the original

Distinguishable without hueShifts in lightness toonever rely on hue alone to carry meaning

Contrast with white, large text4.3:1WCAG large text: AA

Contrast with black, large text4.89:1WCAG large text: AAA

Named colours

Red · ΔE 7 Orange red · ΔE 11.7 Tomato · ΔE 26.1 Crimson · ΔE 29.5 Firebrick · ΔE 33.7 Coral · ΔE 37.1

Nearest named CSS colourRed (#FF0000)ΔE 7.05, clearly different but related

Hue familyred

CSS keyword usableNo exact keyword

Colour harmonies

base +30°+90°+120°+180°+210°+240°+270°+330°

Complementary#09E6F2

Analogous#F20972, #F28909

Triadic#09F215, #1509F2

Split complementary#09F28A, #0971F2

Tetradic#72F209, #09E6F2, #8909F2

Tints, shades & saturation

+40%+30%+20%+10%base -10%-20%-30%-40%

Lighter +40%#FDCDCA

Lighter +30%#FB9E99

Lighter +20%#F96F68

Lighter +10%#F84036

Darker −10%#C11107

Darker −20%#900C05

Darker −30%#5E0804

Darker −40%#2D0402

More saturated +25%#FB0D00

Less saturated −25%#D33128

Channel breakdown

R242

G21

Red242 (94.9%)

Green21 (8.2%)

Blue9 (3.5%)

Hue3.09°

Saturation (HSL)92.83%

Lightness49.22%

Dominant channelRed

Hex per channelR F2 · G 15 · B 09

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Harmonies

Lighter and darker

Similar named colours

Also reads as

F21509 (chemical formula)

Formula
408,627.982 g/mol
21509 atoms

F21509 has a molar mass of 408,627.982 g/mol, made up of 21509 atoms across 1 element: 21509 × F.

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Molar mass

Molar mass408,627.982 g/mol

Total atoms per molecule21509

Distinct elements1

Mass of one molecule6.7854273 × 10^-19 g

Molecules per gram1.4737465 × 10^18

Name

NameNot in the name tablea name cannot be worked out from a formula alone: isomers share formulas, and naming depends on bonding the formula does not show

Composition by mass

F100%

Fluorine (F × 21509)408,627.982 g/mol, 100%

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Elements in this formula

Fluorine

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