100 micrometres

A clickable mosaic of objects
at scales within direct human experience, from the micrometric (10⁻⁶ m, top left) to the multi-kilometric (10⁵ m, bottom right).

To help compare different orders of magnitude, this page lists lengths between 10⁻⁴ m and 10⁻³ m (100 µm and 1 mm).

Distances shorter than 100 µm

• 100 µm – 1/10 of a millimetre
• 100 µm – 0.00394 inches
• 100 µm – average diameter of a strand of human hair^[1]
• 100 µm – thickness of a coat of paint
• 100 µm – length of a dust particle
• 110 µm – half way between the Planck scale and the diameter of the Observable universe,
      √(8.8×10²⁶meters/1.6×10⁻³⁵meters) × 1.6×10⁻³⁵meters=110 µm
• 120 µm – diameter of a human ovum
• 170 µm – length of the largest sperm cell in nature, belonging to the Drosophila bifurca fruit fly^[2][3]
• 181 µm – maximum width of a strand of human hair^[1]
• 100–400 µm – length of Demodex mites living in human hair follicles
• 200 µm – typical length of Paramecium caudatum, a ciliate protist
• 250–300 µm – length of a dust mite^[4]
• 340 µm – length of a single pixel on a 17-inch monitor with a resolution of 1024×768
• 500 µm – typical length of Amoeba proteus, an amoeboid protist
• 500 µm – MEMS micro-engine
• 560 µm - thickness of the central area of a human cornea^[5]
• 760 µm – thickness of an identification card

Distances longer than 1 mm

Notes

1. According to The Physics Factbook, the diameter of human hair ranges from 17 to 181 µm. Ley, Brian (1999). "Width of a Human Hair". The Physics Factbook.
2. Kim Popiolek. "Dr. Charles Lindemann's Lab: Sperm Facts". Oakland University.
3. Santoso, Alex (June 17, 2006). "World's Biggest Sperm Belongs to a Tiny Fly". Neatorama.
4. House Dust Mites HYG-2157-97. Retrieved 2008-12-04
5. "Evaluation of corneal thickness and topography in normal eyes using the Orbscan corneal topography system". Br J Ophthalmol 83 (7): 774–8. July 1999. doi:10.1136/bjo.83.7.774. PMC 1723104. PMID 10381661.