Troy Ounces to Grams
Convert any value from troy ounce to gram with full precision. Use the converter above for instant results, or read on for the exact formula, worked examples, common uses, and answers to frequently asked questions.
📊 Quick Conversion Table
About the Troy Ounce to Gram conversion
Mass and weight conversions come up everywhere — in cooking, shipping, science, fitness, and international trade. Although mass and weight are technically different (mass is the amount of matter, weight is the force gravity exerts on that matter), the everyday conversions between pounds, kilograms, ounces, grams, and stones are what most people need.
This page focuses specifically on converting troy ounce to gram. Use the converter above for instant results, or read on for the exact formula, a worked example, and answers to common questions.
Where this conversion is used
Chefs convert between grams and ounces when following recipes from different countries. Shippers calculate postage and freight using kilograms and pounds. Bodybuilders track weight in pounds or kilograms. Scientists and pharmacists use milligrams, micrograms, and carats for precise measurements. Jewelers rely on troy ounces and pennyweights.
If you frequently convert troy ounce to gram, bookmark this page — the exact URL gives you instant access without searching, and the conversion widget is ready to use the moment the page loads.
Conversion formula
The exact mathematical relationship between troy ounce and gram is:
1 troy ounce = 31.1034768 gram
So to convert a value V from troy ounce to gram, use:
Vgram = Vtroy ounce × 31.1034768
To go in the opposite direction:
Vtroy ounce = Vgram × 0.03215075
These factors come from the international definitions published by NIST, BIPM, and ISO 80000 and are exact within their respective standard systems. The converter applies them with full floating-point precision.
Worked example
Using the formula above, here are some common values converted from Troy Ounce to Gram:
| Troy Ounce | Gram |
|---|---|
| 1 | 31.103477 |
| 5 | 155.517384 |
| 10 | 311.034768 |
| 25 | 777.58692 |
| 50 | 1555.17384 |
| 100 | 3110.34768 |
Sources and accuracy
The kilogram was redefined in 2019 by fixing the Planck constant (NIST, BIPM). All metric mass units derive from this base. The international avoirdupois pound (0.45359237 kg) was agreed in the 1959 international yard and pound agreement between English-speaking nations. Troy weights (used for precious metals) follow the troy system standardized in 1828 by the U.S. Mint.
This page was reviewed against multiple authoritative references. Conversion factors are cross-checked with the NIST SP 811 guide, the BIPM SI brochure, ISO 80000, and where applicable, the historical references for older unit systems. If you spot an inconsistency or have a suggested improvement, please let us know via the contact page.
Important disclaimer: for mission-critical work — medical dosing, legal-for-trade measurements, aerospace, large-scale engineering, and financial calculations — always verify independently with the original source. This converter is intended for everyday conversions, education, and quick reference.
Practical tips
A common source of error is mixing troy and avoirdupois ounces: one troy ounce is about 31.1 g while one avoirdupois ounce is about 28.35 g. Use the troy ounce option only when measuring gold, silver, platinum, or gemstones.
If you are converting large lists of values, use the swap button to instantly reverse direction without retyping. For decimal-heavy values you can paste them directly into the From field — the input accepts standard decimal notation, including negative values and scientific notation (for example, 1.23e-5).
Frequently asked questions
How accurate is this troy ounce to gram converter?
It uses the official international conversion factors from NIST and BIPM with full double-precision floating-point accuracy. For everyday use the result is precise to many more decimal places than any practical measurement requires.
Can I convert in both directions?
Yes. Use the ⇄ button above to swap the From and To fields. You can also change either dropdown to any unit in the weight & mass category.
Do I need an internet connection?
Only for the first page load. Once the converter is loaded it runs entirely in your browser, so it works offline as well.
Is my data private?
Yes. The conversion calculation happens locally in your browser. The values you enter are never sent to any server.