Platinum is quoted in US dollars per troy ounce, but jewelry and small bars are usually weighed in grams. This page shows the conversions and includes a calculator. Enter the current spot price from our live platinum price chart — we deliberately don’t pre-fill a price, so the result is never based on a stale number.
Platinum Price Calculator
The result is the melt value of the platinum content only. Dealers buying scrap typically pay less than this to cover refining and margin, and retail jewelry prices are much higher because they include craftsmanship and markup.
Key Conversion Factors
| Unit | Equivalent |
|---|---|
| 1 troy ounce (ozt) | 31.1034768 grams |
| 1 gram | 0.0321507 troy ounces |
| 1 kilogram | 32.1507466 troy ounces |
| 1 pennyweight (dwt) | 1.55517384 grams (1/20 ozt) |
| 1 avoirdupois ounce | 28.349523 grams (not used for metals) |
The Formulas
- Price per gram = price per troy ounce ÷ 31.1035
- Price per kilogram = price per troy ounce × 32.1507
- Metal value of an item = weight in grams × purity × price per gram
Worked example (illustrative numbers only): if platinum were $1,000 per troy ounce, one gram would be $1,000 ÷ 31.1035 ≈ $32.15. A 10-gram Pt950 ring would contain 9.5 g of platinum worth about 9.5 × $32.15 ≈ $305 at that price.
Platinum Purity Marks
Platinum hallmarks are given in parts per thousand. Pt950 (95%) is the most common jewelry standard in the US and Europe; Pt900 and Pt850 are also used, notably in Japan. Investment bars and coins are typically 999.5 fine or better. Unlike gold, platinum is not described in karats.
Frequently Asked Questions
How many grams are in a troy ounce of platinum?
One troy ounce is 31.1034768 grams.
How do I calculate the platinum price per gram?
Divide the spot price per troy ounce by 31.1035. For a kilogram, multiply the ounce price by 32.1507.
What is Pt950?
Pt950 is a hallmark meaning the item is 950 parts per thousand (95%) platinum, the most common standard for platinum jewelry.
Disclaimer: This article is for general information and education only. It is not investment, tax or financial advice, and it does not recommend buying or selling any asset. Precious metal prices are volatile; past performance does not predict future results. Figures are approximate and should be checked against current primary sources.