US penny
A US penny is a copper-plated coin worth one cent in United States currency.
How big is it?
1.905 cm across
Also 0.750 in
Diameter · specified
Format: Copper-plated zinc. US penny: 19.05 mm (0.750 in) in diameter, 1.52 mm (0.060 in) thick, and 2.5 g in mass. Diameter measures across the face, not the edge thickness.
Check US penny material and older-format differences. Compare UK and US coin dimensions.
A little perspective
US penny vs Sea angel: length comparison
The body length of a sea angel is about 1.05 times the diameter of a US penny.
A US penny is a copper-plated coin worth one cent in United States currency.
A sea angel is a small, transparent swimming sea slug with wing-like appendages, found in cold ocean waters.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions. Horizontal rulers compare the selected spans; vertical brackets also identify height on the artwork.
Measurements, assumptions & sources +
US penny
Diameter: 1.905 cm; specified.
Copper-plated zinc US cent: 19.05 mm diameter, 1.52 mm published thickness and 2.5 g mass. Earlier copper-alloy cents have different masses; transition dates alone do not identify composition.
US Mint — circulating coin specifications
The marked diameter is calibrated. Unmeasured illustration details are representative.
Sea angel
Defined body length: 2 cm; representative specimen; range 1 cm–4 cm.
A defined 2 cm adult sea angel modelled on Clione limacina. Body length excludes the extended wing-like parapodia; species, maturity and posture change the span.
The marked defined body length is calibrated. Unmeasured illustration details are representative.
Use the visual comparison to explore its scale, then check the measurements and sources.
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 1.905 cm
We compare the diameter of a US penny. This value follows a stated specification; check its scope in the notes.
Copper-plated zinc US cent: 19.05 mm diameter, 1.52 mm published thickness and 2.5 g mass. Earlier copper-alloy cents have different masses; transition dates alone do not identify composition.
The marked horizontal span follows the measured feature, not the edges of the image. How calibrated comparisons work →
Recorded properties
Dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 19.05 mm (0.750 in) | Not recorded | specified - Copper-plated zinc | |
| 2.5 g | Not recorded | specified - Copper-plated zinc | |
| 1.52 mm (0.060 in) | Not recorded | specified - Copper-plated zinc |
Around this scale
Explore nearby values.
Compare examples with lower, similar and higher values. Each card names the measurement being compared.
Nearest lower valueEveryday objectsUK 5p coin1.8 cmSpecified diameterA UK 5p coin is the five-pence denomination of the decimal pound sterling circulation coinage.
Around the same scaleEveryday objectsRaspberry2 cmDefined fruit diameterA raspberry is an edible fruit from the Rubus genus, composed of many small drupelets and commonly red in colour.
Nearest higher valueEveryday objects20 × 30 mm stamp2 cmWidthA postage stamp is a small adhesive label placed on mail to show payment for postal services.Sources and method
Want to check the number?
The source records and measurement method remain available for inspection.
- US Mint — circulating coin specificationsNominal format specifications. Direct retrieval returned HTTP 403 during the October 2026 review; additional references identify the thickness values used.
- US penny — composition and dimensions referenceSecondary corroboration of copper-plated zinc cent dimensions: 19.05 mm diameter, 1.52 mm thickness and 2.5 g mass. Direct US Mint retrieval was blocked.
There’s always another scale
Follow your curiosity.
Living thingsSea angel2 cmA sea angel is a small, transparent swimming sea slug with wing-like appendages, found in cold ocean waters.Everyday thingsUK 5p coin1.8 cmA UK 5p coin is the five-pence denomination of the decimal pound sterling circulation coinage.
PeopleHuman eyeball2.4 cmThe human eyeball is the globe-shaped organ that receives light and begins the process of vision.
Everyday thingsUS dime1.791 cmA US dime is a ten-cent coin, the smallest denomination in US currency above the penny and nickel.
Living thingsHoneybee1.5 cmA honeybee is a social insect that lives in a colony and gathers nectar and pollen from flowers.
Everyday thingsUK 1p coin2.03 cmA UK 1p coin is the one-penny denomination of the decimal pound sterling circulation coinage.
SportSquash ball4 cmA squash ball is a small, hollow rubber ball used in the sport of squash.
PeopleFingernail1.5 cmA fingernail is the hard, protective covering at the tip of a human finger, composed of keratin.