Door key
A door key is a small metal tool designed to operate the lock mechanism of a door.
How big is it?
5.5 cm long
Also 2.165 in
Length · example
A little perspective
About the same scale as Cleaner shrimp.
Cleaner shrimp: A cleaner shrimp is a marine crustacean that removes parasites and dead tissue from fish, forming mutualistic relationships.
Measurements, assumptions & sources +
Door key
A chosen 55 mm, 9 g household key.
Defined examples — our methodology
The marked length is calibrated. Unmeasured illustration details are representative.
Cleaner shrimp
A defined 5.5 cm skunk cleaner shrimp measured from rostrum to tail fan. Long white antennae extend beyond and are excluded from body length.
Smithsonian Ocean — Cleaner shrimp
The marked defined body length is calibrated. Unmeasured illustration details are representative.
Change your perspective
Put it next to…
Choose a suggestion to redraw the comparison, or open its page to learn what it is.
Why this measurement?
Why we use 5.5 cm
For comparison, this page uses length. This is labelled example: an explicit comparison model rather than a claim that every example has the same value.
A chosen 55 mm, 9 g household key.
The marked vertical span follows the named feature; transparent margins and unmeasured details do not alter it. How calibrated comparisons work →
Recorded properties
Door key dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 5.5 cm | Not recorded | example | |
| 9 g | Not recorded | example |
Around this scale
Go smaller. Go bigger.
These links use compatible length records, ordered around the selected value.
Nearest lower value · Everyday thingsPlum5 cmA plum is a sweet, edible fruit produced by trees of the genus Prunus, containing a single hard stone.
Around the same scale · Living thingsCleaner shrimp5.5 cmA cleaner shrimp is a marine crustacean that removes parasites and dead tissue from fish, forming mutualistic relationships.
Nearest higher value · SportPelota ball5.7 cmA pelota ball is a hard ball used in Basque pelota, a traditional court sport played by striking the ball against a wall.Sources and method
Want to check the number?
The source records and measurement method remain available for inspection.
More ways to see it
Curated comparisons
There’s always another scale
Follow your curiosity.
PeopleHuman1.75 mA human is a primate of the species Homo sapiens, distinguished by habitual upright walking, language and complex tool use.
TransportFamily car4.5 mA family car is a motor vehicle designed to carry several passengers and their belongings.
TransportDouble-decker bus11 mA double-decker bus is a passenger vehicle with two levels, used for public transport.Living thingsCleaner shrimp5.5 cmA cleaner shrimp is a marine crustacean that removes parasites and dead tissue from fish, forming mutualistic relationships.Everyday thingsPlum5 cmA plum is a sweet, edible fruit produced by trees of the genus Prunus, containing a single hard stone.
SportLacrosse ball6.35 cmA lacrosse ball is a solid rubber ball used in the sport of lacrosse, designed to meet official standards for play.
ContainersEspresso demitasse60 mlAn espresso demitasse is a small porcelain cup used for serving concentrated espresso coffee.
Living thingsAntarctic krill6 cmAntarctic krill (Euphausia superba) are small, shrimp-like marine crustaceans that serve as a vital food source for many Antarctic animals.