A troy ounce is exactly 31.1034768 grams.
Troy ounces to Drams Converter — oz t to dr
Convert Troy ounce (oz t) to Dram (dr) using the exact conversion factor (1 troy ounce = 17.55428571 dram). See the formula, worked examples, and conversion table.
Troy ounces to Drams converter
Converter
Mass/Weight Converter
Convert SI mass, imperial weight, jewelry, atomic, and astronomy mass units.
Context values
Some unit families need one extra value for a physically accurate result.
An avoirdupois dram is 1/16 ounce.
Result = input x 0.0311034768 / 0.001771845195.
Mass uses the kilogram as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Troy ounces to Drams
Weight conversions between Troy ounce and Dram come up constantly in everyday commerce, shipping, and cooking, since US packaging is usually labeled in pounds while most of the rest of the world uses kilograms. Specifically: A troy ounce is exactly 31.1034768 grams, and an avoirdupois dram is 1/16 ounce.
Formula
drams = troy ounces × 17.5542857143
This factor comes from each unit's defined relationship to the category's base unit: 1 troy ounce equals 0.0311034768 base units, and 1 dram equals 0.00177184519531 base units, so dividing one by the other gives the direct troy ounce-to-dram factor of 17.5542857143.
Simple example
1 oz t × 17.55428571 = 17.55428571 dr
1 troy ounce = 17.55428571 drams.
Real-world example
50 oz t × 17.55428571 = 877.7142857 dr
50 troy ounces = 877.7142857 drams.
Conversion table
| Troy ounce (oz t) | Dram (dr) |
|---|---|
| 1 oz t | 17.55428571 dr |
| 5 oz t | 87.77142857 dr |
| 10 oz t | 175.5428571 dr |
| 25 oz t | 438.8571429 dr |
| 50 oz t | 877.7142857 dr |
| 100 oz t | 1,755.428571 dr |
Reverse conversion: Dram to Troy ounce
17.55428571 dr × 0.05696614583 = 0.9999999998 oz t
17.55428571 drams = 0.9999999998 troy ounces.
troy ounces = drams × 0.0569661458333
For a page dedicated to this direction, see Dram to Troy ounce.
Understanding the Troy ounce (oz t)
A troy ounce is exactly 31.1034768 grams.
Understanding the Dram (dr)
An avoirdupois dram is 1/16 ounce.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many drams are in 1 troy ounce?
1 troy ounce equals 17.55428571 drams, using the exact defined conversion factor rather than an estimate.
How do I convert troy ounce to dram?
Multiply the troy ounce value by 17.55428571. The converter above does this instantly to whatever precision you set.
How do I convert dram back to troy ounce?
Use the reverse factor: 1 dram equals 0.0569661458 troy ounces. You can also use the swap control in the converter above to flip the direction instantly.
What is a troy ounce?
Troy ounce (oz t) is a unit of mass/weight.
What is a dram?
Dram (dr) is a unit of mass/weight.
Is the troy ounce to dram conversion exact?
Yes. Both troy ounce and dram are defined by fixed standards rather than physical artifacts, so the factor of 17.55428571 used above is exact to as many digits as you choose to display.