Convert Troy Ounce to Milligram
Convert troy ounces to milligrams instantly. 1 troy ounce = 31103.4768 milligram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Milligram to Troy Ounce converter for the reverse conversion.
Units explained
Troy Ounce
The troy ounce (ozt) equals about 31.103 grams, one-twelfth of a troy pound.
From the Troy system of weights associated with Troyes, France.
The global standard for pricing gold, silver, platinum, and palladium.
Established in the medieval Troy system and retained for precious metals.
Milligram
A milligram (mg) equals one-millionth of a kilogram, or 0.001 gram.
From the SI prefix 'milli-' (from Latin 'mille', thousand).
Standard for medicine dosing, nutrition labels, and fine jewelry.
Part of the original metric system of 1795.
Troy Ounce to Milligram conversion formula
The relationship between troy ounces and milligrams:
To convert troy ounces to milligrams, multiply the value in troy ounces by 31103.4768. To reverse, multiply milligrams by 3.215075e-5.
How to use this converter
Type a value into the calculator. The result in milligrams updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Milligram to Troy Ounce converter for the reverse direction.
Step-by-step: convert troy ounces to milligrams
- Write down the value in troy ounces (oz t).
- Multiply that value by the factor 31103.4768.
- The product is the equivalent value in milligrams (mg).
- To reverse, multiply the milligram value by 3.215075e-5.
Worked examples
Example 1 — Convert 1 oz t to mg:
1 × 31103.4768 = 31103.4768 mg
Example 2 — Convert 100 oz t to mg:
100 × 31103.4768 = 3110347.6800000006 mg
Real-world example — Adjacent small-scale precision
One troy ounce equals 1,000 milligrams — the standard sub-millimeter precision conversion that materials engineers use whenever they switch between bulk material thickness specs (larger unit) and surface-finish characteristics (smaller unit).
1 oz t × 31103.4768 = 31103.4768 mg
Real-world example — Adjacent metric sub-units
One troy ounce equals 1,000 milligrams. Engineers move between these scales constantly: PCB feature sizes in the larger unit, wire-bond diameters in the smaller.
1 oz t × 31103.4768 = 31103.4768 mg
Troy Ounce to Milligram conversion table
Standard reference values for converting troy ounces to milligrams:
| Troy Ounce [oz t] | Milligram [mg] |
|---|---|
| 0.01 | 311.034768 |
| 0.1 | 3110.34768 |
| 1 | 31103.4768 |
| 2 | 62206.9536 |
| 3 | 93310.4304 |
| 4 | 124413.9072 |
| 5 | 155517.384 |
| 10 | 311034.768 |
| 20 | 622069.5360000001 |
| 30 | 933104.3040000001 |
| 40 | 1244139.0720000002 |
| 50 | 1555173.8400000003 |
| 100 | 3110347.6800000006 |
| 500 | 1.555174e+7 |
| 1000 | 3.110348e+7 |
Frequently asked questions
How many milligrams is 1 troy ounce?
How do I convert troy ounces to milligrams?
How do I convert milligrams back to troy ounces?
How many milligrams is 100 troy ounces?
Popular weight unit conversions
Convert Troy Ounce to other weight units
Show all Troy Ounce conversions
Metric / SI (18 units)
Avoirdupois (15 units)
Troy & Apothecary (9 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Sources & references
Conversion factor (1 oz t = 31103.4768 mg) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.