Silver Weight Calculator
Weighing a silver bar, coin, sheet, or wire accurately is a common need for bullion collectors, jewelers, refiners, and estate appraisers. This silver weight calculator uses the published density of each common purity (from .900 coin silver to .999 fine) and your measured dimensions to return the weight in grams, troy ounces, avoirdupois ounces, and pounds, plus an estimated melt value from the current spot price.
How the Silver Weight Calculator Works
Silver weight is mass, and mass equals volume times density. The calculator handles four shape geometries:
- Bar / ingot: length x width x thickness (rectangular prism)
- Round / coin: pi x (diameter / 2)^2 x thickness (disc)
- Sheet / plate: same as bar
- Wire / rod: pi x (diameter / 2)^2 x length (cylinder)
All dimensions are converted to centimetres, multiplied to get volume in cm^3, then multiplied by the density of your chosen purity to get mass in grams. One troy ounce equals 31.1034768 grams. A pound is 453.59237 grams.
Silver Density by Purity
| Purity | Fineness | Density (g/cm^3) | Common Use |
|---|---|---|---|
| .999 Fine | 99.9% Ag | 10.49 | Bullion, rounds, bars, wire |
| .958 Britannia | 95.8% Ag | 10.44 | UK post-1999 silver coins |
| .925 Sterling | 92.5% Ag | 10.36 | Jewelry, flatware, hollowware |
| .900 Coin | 90.0% Ag | 10.32 | US coins pre-1965, Morgan/Peace dollars |
Pure silver is soft. The non-silver balance is almost always copper, which is slightly denser than silver, so lower purities are a hair lighter per unit volume, not heavier. The density numbers above are the industry standard values used by the LBMA, refineries, and mints.
Troy Ounce vs Regular Ounce
This is the single most common silver weight mistake. A troy ounce (t oz) is 31.1034768 g. A regular (avoirdupois) ounce is 28.3495 g. Silver, gold, platinum, and palladium are always sold by the troy ounce. A "1 ounce" silver round is actually 31.1 g, not 28.3 g. The calculator shows both so you can verify a scale reading either way.
Pure Silver Content and Melt Value
Pure silver content is the total weight multiplied by the fineness. A 100 g sterling bar contains 92.5 g of actual silver. Multiply that pure-silver weight (in troy ounces) by the spot price to get the melt value. The spot price is what a refiner pays for the silver content alone; retail buyers pay a premium above spot, and dealers pay below spot for scrap.
Silver Weight Calculator App Note
This silver weight calculator app runs entirely in your browser. There is nothing to install, no login, no tracking. Dimensions, purity, and spot price stay on your device. Bookmark the page or add it to your home screen for quick access on the bench or at a coin show.
Common Silver Weight Reference Values
- American Silver Eagle: 31.103 g (1 t oz) .999
- US Morgan/Peace silver dollar: 26.73 g (0.7735 t oz pure) .900
- Sterling teaspoon (typical): 20-30 g depending on pattern, .925
- 1 kg silver bar .999: 1000 g = 32.15 t oz
- 10 oz silver bar .999: 311.03 g (10 t oz)
If your measured weight is more than 2-3% off these references for a known-genuine item, the piece may be plated, hollow, or counterfeit. For collector-grade verification, combine weight, diameter, and thickness against mint specifications.