Recognised as Colour
#FF211F
- #FF211F
- Red
- Dark
- Nearest: Red
#FF211F is a red with RGB values 255, 33, 31 and HSL 1°, 100%, 56%. It is a dark colour, so black text on it reaches 5.5:1 contrast (AA for normal text). The nearest named colour is Red.
Colour values
#FF211F#FF211F
HEX#FF211F
RGBrgb(255, 33, 31)
RGB (0–1)1, 0.1294, 0.1216
RGB percentages100%, 12.9%, 12.2%
HSLhsl(0.5, 100%, 56.1%)
HSV / HSBhsv(0.5, 87.8%, 100%)
CMYK0%, 87.1%, 87.8%, 0%≈naive device-independent conversion; real print needs an ICC profile
24-bit integer16,720,159
CSS custom property--colour: #FF211F;
Brightness & contrast
Relative luminance0.22447WCAG 2.x, 0 is black and 1 is white
Perceived brightness142.1 of 255ITU-R BT.601 weighting
Light or darkDark
Best text colour on this backgroundBlackcontrast 5.49:1
Contrast with white3.83:1WCAG normal text: Fail
Contrast with black5.49:1WCAG normal text: AA
Greyscale equivalent#505050
Inverted#00DEE0
Colour vision & accessibility
Distinguishable without hueShifts in lightness toonever rely on hue alone to carry meaning
Contrast with white, large text3.83:1WCAG large text: AA
Contrast with black, large text5.49:1WCAG large text: AAA
Named colours
Hue familyred
CSS keyword usableNo exact keyword
Colour harmonies
Complementary#1FFDFF
Analogous#FF1F8D, #FF911F
Triadic#1FFF21, #211FFF
Split complementary#1FFF91, #1F8DFF
Tetradic#8DFF1F, #1FFDFF, #911FFF
Tints, shades & saturation
Channel breakdown
R255
G33
B31
Red255 (100%)
Green33 (12.9%)
Blue31 (12.2%)
Hue0.54°
Saturation (HSL)100%
Lightness56.08%
Dominant channelRed
Hex per channelR FF · G 21 · B 1F
Keep nerding
Every link below is a page Nerdulator can generate from what it already knows about this value.
Also reads as
FF211F (chemical formula)
- Formula
- 4,046.574 g/mol
- 213 atoms
FF211F has a molar mass of 4,046.574 g/mol, made up of 213 atoms across 1 element: 213 × F.
Molar mass
Molar mass4,046.574 g/mol
Total atoms per molecule213
Distinct elements1
Mass of one molecule6.7194942 × 10^-21 g
Molecules per gram1.4882072 × 10^20
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 × 213)4,046.574 g/mol, 100%
Keep nerding
Every link below is a page Nerdulator can generate from what it already knows about this value.
Elements in this formula
Nerdulate something else
Nothing in mind? Surprise me · today’s page