Head louse (Adult)
2.5 mm (0.09843 in)
Adult body length
The wingless insect that lives in human hair, seen from above. 2 to 3 mm long.
Published
How big is that?
2.5 mm is 36 times the width of a human hair and 35% of a grain of rice.
Head louse is the 11th largest of the 32 Tiny Worlds objects, and the 22nd smallest of the 172 objects across all five SizeItUp games.
Closest in size from the other games: Black peppercorn (Kitchen Table), 4.865 mm across.
Size comparison
To scale, smallest to largest: Head louse in orange beside the Tiny Worlds objects nearest in size, in teal.
| Object | Size | vs Head louse |
|---|---|---|
| Chia seedA small speckled seed from Salvia hispanica. | 1.96 mm long | 78% of the size |
| Cat fleaThe flea found on cats and dogs, flattened side to side for slipping through fur. | 2 mm long | 80% of the size |
| Argentine ant (Worker)A tiny brown ant that forms supercolonies, seen from the side. All workers are one size. | 2.5 mm long | about the same |
| Head louse (Adult) | 2.5 mm long | – |
| Sesame seedA flat, teardrop seed from the sesame plant. | 2.96 mm long | 1.2× bigger |
In other units
| Millimetres | 2.5 |
|---|---|
| Centimetres | 0.25 |
| Metres | 0.0025 |
| Inches | 0.09843 |
How it's measured
Adult body length. Midpoint of 2 to 3 mm (US CDC).
The source gives a range, so this is the middle of it.
Sources
- cdc.gov: US CDC: adult head lice are roughly 2 - 3 mm long.
Checked against the source on .
Could you have guessed it by eye?
Head louse is one of the objects in Tiny Worlds, a daily size comparison game: you stretch a shape to the size you think is right beside one you know.