How large is a quarter? Quarters are a familiar type of coin that is widely used. But have you ever stopped to consider exactly how big they are? In this comprehensive guide, we will explore every dimension of the quarter to give you a detailed understanding of its size.
If you’re short on time, here’s a quick answer: a quarter has a diameter of 24.26 mm (0.955 inches) and a thickness of 1.75 mm (0.069 inches).
Read on as we dive into the specifics behind the quarter’s measurements, from diameter to volume to weight. We’ll also compare it to other coins and everyday objects so you can get a vivid sense of just how large a quarter truly is.
The Diameter of a Quarter
Diameter in Millimeters
The diameter of a standard United States quarter measures 24.26 mm. This size has remained consistent since the introduction of the Washington quarter in 1932. The quarter is composed of a copper-nickel alloy called cupronickel which lends durability and resistance to corrosion.
To put the quarter’s diameter in perspective, it’s slightly smaller than an Australian 50-cent coin (31.5 mm) but larger than a British 20-pence coin (21.4 mm). Many vending machines, parking meters, and other automated systems are designed with the standard quarter diameter in mind.
Diameter in Inches
When converted to inches, the diameter of a quarter is 0.955 inches. Simply put, just shy of 1 inch. This places it between the dime (0.705 inches) and half a dollar (1.205 inches) in terms of size.
Consistent sizing is important for use in coin mechanisms as mentioned earlier. However, errors in striking at the United States Mint have produced some quarters with defects. These can range from clipped edges to partial off-center strikes that affect the quarter’s intended diameter.
The Thickness and Edge of a Quarter
Thickness
The thickness of a United States quarter is approximately 1.75mm, which converts to 0.069 inches. This slim profile makes quarters easy to stack and carry while still maintaining a substantial feel during use. The uniform thickness also allows vending machines to easily accept and process quarters.
Quarters minted prior to 1965 contain an average of 90% silver and 10% copper. These coins are approximately 20% thicker to accommodate this change in metal composition. Pre-1965 quarters measure 2.15mm or 0.085 inches thick.
When the United States switched compositions to a clad sandwich of copper and nickel in 1965, the thinner 1.75mm dimension became standard.
For comparison, a standard U.S. dime is 1.35mm (0.053 inches) thick while a nickel is 1.95mm (0.077 inches). So a quarter falls neatly between the smaller dime and thicker nickel in overall thickness. This graduated size helps with identification during transactions.
Quarters are the thickest of the three coins smaller than a half-dollar.
Reeded Edge
The outside edge of a quarter contains reeding – closely spaced ridges around the circumference on both the obverse and reverse faces. These tiny grooves help prevent counterfeiting and make the quarter easier to grip when selecting from a stack of coins.
A United States quarter contains 119 reeds around the entire outer edge. Each reed is approximately 0.25mm tall. The reeding extends from the surface on each face to meet in the middle at the side of the coin. So only about half the quarter’s thickness contains the reeded design.
Reeding first appeared on US coinage in the early 1800s. It helped prevent thieves from shaving small amounts of precious metal from the edges. Prior to reeding, coin edges were plain and susceptible to undetectable paring. The ribbed edges halted this practice by showcasing any missing metal.
The number of reeds per coin has changed throughout history. Early quarters had either 116 or 132 reeds. But 119 became standard in the 1930s and continues on quarters today. The ridges are compressed during production on coin press machines calibrated for uniform spacing.
| Measurement | Dimension |
| Diameter | 24.26 mm (0.955 in) |
| Thickness | 1.75 mm (0.069 in) |
| Weight | 5.67 g (0.2 oz) |
| Reeds | 119 |
Coins with reeded edges like the quarter are sometimes called “reeded coins” or “reeded coinage.” The ridges help anchor the metal to prevent warping and wear. They also give the coin a textured feel and distinctive look recognizable during hurried transactions.
To learn more about quarter dimensions and specifications, visit the U.S. Mint’s page on quarters.
The Weight of a Quarter
A United States quarter dollar coin, commonly called a “quarter”, weighs exactly 5.670 grams. This weight has remained consistent since the Coinage Act of 1965 standardized the weights and compositions of US coins.
To put the weight of a quarter into perspective:
- A stack of 4 quarters weighs about 1 ounce
- 1 pound contains approximately 155 quarters
- 1 metric ton of quarters would be worth $5.6 million dollars
The quarter gets its weight from its metal composition. Since 1965, most circulating quarters have been made from an alloy that is 91.67% copper and 8.33% nickel. This alloy was selected because it has excellent wear characteristics, satisfying the need for durable coins.
Interestingly, from 1796 to 1964, U.S. quarters were made from 90% silver and 10% copper. These silver quarters were significantly heavier at 6.25 grams each. However, the rising price of silver forced the switch to the current copper-nickel alloy.
The consistent 5.670-gram weight makes the quarter a convenient base unit for commerce. Retail goods are often priced to require an exact number of quarters, with taxes included. Vending machines and laundromats also rely on the standard quarter weight to accurately set prices and deliver services.
The Volume and Surface Area
Volume
A standard United States quarter has a diameter of 24.26 mm and a thickness of 1.75 mm. Using these dimensions, we can calculate the volume of a quarter.
The formula for the volume of a cylinder is:
- V = πr2h
Where V is the volume, π is the constant Pi (3.14159), r is the radius of the base, and h is the height or thickness. The radius can be calculated from the diameter (d = 2 x r) so the equation becomes:
- V = π(d/2)2h
Plugging in the dimensions of a quarter with a diameter of 24.26 mm and a thickness of 1.75 mm:
- V = 3.14159 x (24.26 ÷ 2)2 x 1.75
- V = 3.14159 x 12.132 x 1.75
- V = 658.99 mm3 (0.659 mL or 0.0658 fluid ounces)
Surface Area
The surface area of a cylinder includes the area of the top and bottom (the bases) and the lateral surface area around the side. Where A is the total surface area, πr2 is the base area, and the lateral area around the side is the circumference (2πr) times the height h.
| Base area (top and bottom) | = 2 πr2 |
| Lateral surface area | = 2πrh |
| Total surface area | = 2πr2 + 2πrh |
Using the dimensions of a quarter where diameter (d) is 24.26mm:
- Radius (r) is d/2 = 12.13 mm
- Height (h) is 1.75 mm
Plugging this into the equation:
- Base area = 2 x 3.14159 x (12.13 mm)2 = 1163.15 mm2
- Lateral area = 2 x 3.14159 x (12.13 mm) x (1.75 mm) = 106.94 mm2
- Total surface area = 1163.15 + 106.94 = 1270.09 mm2
A quick reality check shows that 4 quarters placed together have a combined surface area very close to that of a standard 3′′ x 3′′ sticky note, making sense since their diameters are similar.
How a Quarter Compares to Other Coins and Objects
Comparison to Other Coins
With a diameter of 24.26 mm (0.955 inches) and a thickness of 1.75 mm (0.069 inches), the quarter is somewhat larger than the nickel, dime, and penny but smaller than the half dollar. Here’s how the quarter stacks up against some other U.S. coins:
| Coin | Diameter | Thickness |
|---|---|---|
| Penny | 19.05 mm | 1.52 mm |
| Nickel | 21.21 mm | 1.95 mm |
| Quarter | 24.26 mm | 1.75 mm |
| Half Dollar | 30.61 mm | 2.15 mm |
Although the quarter has reigned supreme for decades, its purchasing power has gradually declined over time. According to the U.S. Bureau of Labor Statistics (2023), a quarter in 2023 has the same purchasing power as just 8 cents in 1950!
Comparison to Everyday Objects
To give some perspective on the quarter’s size, here are some comparisons to common everyday objects:
- The quarter is slightly larger in diameter than an AA battery
- It’s about the same diameter as a zinc screw or an unsharpened pencil
- Stacked in one column, 4 quarters measure roughly the same height as the average computer mouse
- In terms of weight, 25 quarters amount to about 1/3 pound
With its considerable heft and size, the quarter can definitely feel like a chunky piece of change in your pocket!
How Large Is A Quarter – Conclusion
We have explored the quarter inside and out, looking at key measurements like diameter, thickness, weight, and volume. Comparing it along the way to other coins and common objects provides a tangible sense of its size.
So the next time you’re holding a quarter, you’ll have a whole new appreciation for its precise dimensions and how they stack up. Understanding the details of this little coin makes an everyday carry that much more interesting!
