Troy Ounce to Grams Converter — Live Gold Money Value
A troy ounce is the international standard unit for precious metals: 1 troy ounce (oz t) = 31.1034768 grams (commonly rounded to 31.1035 g). It is heavier than the avoirdupois ounce used for groceries (28.3495 g) — confusing two ounces by 10% leads to large valuation errors when buying or selling gold.
This converter takes a troy-ounce input and returns the exact gram weight, the equivalent in pennyweight (1 troy oz = 20 dwt), grains (1 troy oz = 480 grains), tola (1 troy oz = 2.6667 tola), and the money value at the live international XAU/USD spot rate.
How the conversion works
Grams = Troy ounces × 31.1034768. Money value = Troy ounces × live XAU/USD spot price (the spot rate is already troy-ounce denominated, so this is the simplest of the conversions). For local currency: Money = (Troy oz × spot $) × FX rate.
Sample conversions
| Input | Result |
|---|---|
| 1 troy ounce | 31.1035 g (= 20 dwt = 480 grains) |
| 1 troy ounce | 2.6667 tola = 32 masha = 256 ratti |
| 5 troy ounces | 155.517 g (= 100 dwt) |
| 10 troy ounces | 311.035 g (= 1 troy pound) |
| 32.1507 troy oz | 1,000 g = 1 kg (typical retail bullion bar) |
When to use this calculator
- International bullion trade — COMEX, LBMA, ICE Futures and major refiners (PAMP, Valcambi, Argor-Heraeus) all quote troy ounces.
- Coin investment — Krugerrand, Maple Leaf, American Eagle and Vienna Philharmonic are 1 troy oz (and fractional 1/2, 1/4, 1/10 oz coins).
- ETF/futures correlation — gold ETFs (GLD, IAU, etc.) hold troy-ounce inventories; checking parity requires converting share holdings to gram-equivalent.
- Refiner intake — most international refiners accept gross weight in grams but pay out in troy ounces of pure gold recovered.
Frequently asked questions
Why is a troy ounce different from a regular ounce?
The troy ounce comes from the medieval Troyes market (France) where precious-metal weight was distinguished from grocery weight. Troy ounce = 31.1035 g; avoirdupois (regular) ounce = 28.3495 g. The difference is ~10%, large enough to cause expensive mistakes — always specify "troy" when discussing gold or silver.
How many troy ounces in a kilogram of gold?
1 kg = 32.1507 troy ounces (1000 ÷ 31.1035). A standard retail "kilobar" therefore contains slightly more than 32 troy oz, which is why kilobars trade at a small premium to the equivalent number of 1-oz coins.
Is a 1 oz American Gold Eagle really 1 troy ounce of pure gold?
The Gold Eagle contains exactly 1 troy ounce of pure gold (31.1035 g) — but its gross weight is 33.93 g because it is alloyed at 22K (91.67%) for durability. Compare to Maple Leaf and Buffalo coins, which are 24K (99.99%) and weigh exactly 31.1035 g gross.