21 inches

TV & monitor size

16.8 x 12.6 in

Aspect ratio 4:3

Aspect ratio 5:4

Aspect ratio 16:9

Aspect ratio 16:10

Aspect ratio 21:9

Aspect ratio 32:9

Metric

  • Kilometre (km)
    4.27×10⁻⁴ x 3.2×10⁻⁴
  • Metre (m)
    0.43 x 0.32
  • Decimetre (dm)
    4.27 x 3.2
  • Centimetre (cm)
    42.67 x 32
  • Millimetre (mm)
    426.72 x 320.04
  • Micrometre (µm)
    426,720 x 320,040
  • Nanometre (nm)
    426,720,000 x 320,040,000
  • Angstrom (Å)
    4.27×10⁹ x 3.2×10⁹

British/American

  • League
    8.84×10⁻⁵ x 6.63×10⁻⁵
  • Mile (mi)
    2.65×10⁻⁴ x 1.99×10⁻⁴
  • Furlong
    2.12×10⁻³ x 1.59×10⁻³
  • Chain
    0.02 x 0.02
  • Rod (rd)
    0.08 x 0.06
  • Yard (yd)
    0.47 x 0.35
  • Foot (ft)
    1.4 x 1.05
  • Link
    2.12 x 1.59
  • Hand
    4.2 x 3.15
  • Inch (in)
    16.8 x 12.6
  • Line
    168 x 126
  • Mil (mil)
    16,800 x 12,600
  • Thou (thou)
    16,800 x 12,600

Nautical

  • Nautical mile
    2.3×10⁻⁴ x 1.73×10⁻⁴
  • Fathom
    0.23 x 0.18

Astronomical

  • Parsec (pc)
    1.38×10⁻¹⁷ x 1.04×10⁻¹⁷
  • Light year
    4.51×10⁻¹⁷ x 3.38×10⁻¹⁷
  • Astronomical unit (AE)
    2.85×10⁻¹² x 2.14×10⁻¹²
  • Light minute
    2.37×10⁻¹¹ x 1.78×10⁻¹¹
  • Light second
    1.42×10⁻⁹ x 1.07×10⁻⁹