1 troy ounce = 31.1034768 grams
Precious metals trade exclusively in troy ounces, and confusing the troy ounce with the ordinary ounce overstates a gold holding by nearly 10 percent — a mistake worth several hundred dollars per ounce at current prices.
Formula g = oz t × 31.1034768
Type in either field — the other updates on every keystroke. Need other units? Open the full weight converter.
| Troy ounce | Gram |
|---|---|
| 1 oz t | 31.103477 g |
| 2 oz t | 62.206954 g |
| 3 oz t | 93.31043 g |
| 4 oz t | 124.413907 g |
| 5 oz t | 155.517384 g |
| 10 oz t | 311.034768 g |
| 15 oz t | 466.552152 g |
| 20 oz t | 622.069536 g |
| 25 oz t | 777.58692 g |
| 50 oz t | 1555.17384 g |
| 100 oz t | 3110.34768 g |
| 500 oz t | 15551.7384 g |
| 1000 oz t | 31103.4768 g |
| Gram | Troy ounce |
|---|---|
| 1 g | 0.032151 oz t |
| 2 g | 0.064301 oz t |
| 3 g | 0.096452 oz t |
| 4 g | 0.128603 oz t |
| 5 g | 0.160754 oz t |
| 10 g | 0.321507 oz t |
| 15 g | 0.482261 oz t |
| 20 g | 0.643015 oz t |
| 25 g | 0.803769 oz t |
| 50 g | 1.607537 oz t |
| 100 g | 3.215075 oz t |
| 500 g | 16.075373 oz t |
| 1000 g | 32.150747 oz t |
| Situation | From | To |
|---|---|---|
| Tenth-ounce coin | 0.1 ozt | 3.11 g |
| Half ounce | 0.5 ozt | 15.55 g |
| One ounce | 1 ozt | 31.1 g |
| Five ounces | 5 ozt | 155.5 g |
| Ten-ounce bar | 10 ozt | 311 g |
| One kilogram | 32.1507 ozt | 1,000 g |
Multiply by 31, which reads about 0.3% low. 10 ozt is about 310 g, against an exact 311.03.
Gold, silver, platinum and palladium are priced per troy ounce. Coins and bars are labelled in troy ounces or grams.
A troy ounce (31.1035 g) is about 9.7% heavier than an everyday ounce (28.3495 g), and a troy pound has only 12 ounces. Never use the everyday ounce for bullion.
The name is usually traced to the French market town of Troyes. The troy ounce is exactly 31.1034768 g, or 480 grains.
A troy ounce (31.1035 g) is about 9.7% heavier than an avoirdupois ounce (28.3495 g), and gold, silver, platinum and palladium are priced per troy ounce.
Related guides: Imperial vs metric: differences and quick conversion tricks · Troy vs avoirdupois ounces: the weight of precious metals