Grams to Ounces Converter
Convert grams to regular avoirdupois ounces or ounces to grams with the exact relationship 1 oz = 28.349523125 g. Choose decimal places or significant figures, inspect the exact value, and see pounds-and-ounces, metric and troy-ounce comparisons.
- Exact rational arithmetic
- Two conversion directions
- Decimal or significant-figure rounding
- Regular ounce clearly identified
Convert Grams and Ounces
Enter a nonnegative decimal, scientific-notation value, simple fraction or mixed number. The converter keeps the defined ounce-to-gram factor exact and rounds only the displays you select.
1 g converted with the exact avoirdupois-ounce definition.
Calculation Steps
- Use 1 avoirdupois ounce = 28.349523125 grams exactly.
- Multiply 1 g by 1600000/45359237 to obtain the exact ounce value.
- Apply the selected six-place display only after conversion.
- Round total ounces independently to the selected 1/64-ounce increment for the compound view.
The unit factor is exact. Decimal and compound-unit display settings do not add accuracy to the original measurement.
The browser blocked automatic copying. The complete result is selected. Press Ctrl+C on Windows or Command+C on macOS.
How to Use This Grams to Ounces Converter
Allow about two minutes for one conversion, including a quick check of the ounce system and reporting precision.
- Select the direction. Choose grams to ounces or ounces to grams.
- Enter one mass. Use a decimal such as 100, scientific notation such as 1e3, a fraction such as 1/2, or a mixed number such as 1 1/2. Leave the unit symbol out.
- Choose display precision. Select decimal places or significant figures, enter the required count, and choose a tie rule.
- Select an ounce increment. Choose 1 ounce through 1/64 ounce for the pounds-and-ounces view.
- Press Convert. Review the rounded answer, exact target value, high-precision comparison, mass equivalents and calculation steps.
- Copy, swap or reset. Copy the complete result, swap directions without using a rounded display, or restore the default 1 g example.
Zero is valid. A negative entry is rejected because this tool converts physical mass, not a signed change. In significant-figures mode, trailing zeros show the requested display precision. Fractions and mixed numbers remain exact rational values through the conversion.
How to Convert Grams to Ounces
One regular avoirdupois ounce equals exactly 28.349523125 grams. To convert grams to ounces, divide the gram value by 28.349523125. The same operation multiplies by the exact reciprocal fraction 1600000/45359237.
The reciprocal has a nonterminating decimal expansion beginning 0.0352739619495804. Short factors such as 0.0353 are estimates. This converter keeps the rational factor internally and rounds only the final display.
How to convert ounces to grams
Multiply regular ounces by exactly 28.349523125. Written as an integer ratio, the factor is 45359237/1600000.
For example, 8 oz equals exactly 226.796185 g as the mathematical conversion of the entered value. A scale reading may justify fewer reported digits.
Grams and Ounces Worked Examples
Example 1: Convert 1 gram to ounces
Divide 1 by 28.349523125. The exact result is 1600000/45359237 oz. Its decimal expansion begins 0.0352739619495804, so 1 g is approximately 0.035274 oz at six decimal places.
Example 2: Convert 100 grams to ounces
One hundred grams multiplied by the exact reciprocal equals approximately 3.52739619496 oz. Rounded to two decimal places, this is 3.53 oz. Do not multiply an already rounded 3.53 oz value again when accuracy matters.
Example 3: Convert 250 grams to ounces
Two hundred fifty grams equals approximately 8.8184904874 oz. At the nearest 1/64 ounce, the compound display is about 0 lb 8 13/16 oz.
Example 4: Convert 1 ounce to grams
One avoirdupois ounce equals exactly 28.349523125 g. Sixteen ounces equal exactly 453.59237 g, which is one avoirdupois pound.
Grams to Ounces Conversion Tables
The ounce values below are rounded to six decimal places. The converter retains the exact factor before applying this table display.
| Grams | Ounces | Display status |
|---|---|---|
| 1 g | 0.035274 oz | Approximate |
| 5 g | 0.176370 oz | Approximate |
| 10 g | 0.352740 oz | Approximate |
| 25 g | 0.881849 oz | Approximate |
| 50 g | 1.763698 oz | Approximate |
| 100 g | 3.527396 oz | Approximate |
| 250 g | 8.818490 oz | Approximate |
| 500 g | 17.636981 oz | Approximate |
| 1000 g | 35.273962 oz | Approximate |
Ounces to grams table
| Ounces | Grams | Pounds |
|---|---|---|
| 0.5 oz | 14.1747615625 g | 0.03125 lb |
| 1 oz | 28.349523125 g | 0.0625 lb |
| 2 oz | 56.69904625 g | 0.125 lb |
| 4 oz | 113.3980925 g | 0.25 lb |
| 8 oz | 226.796185 g | 0.5 lb |
| 16 oz | 453.59237 g | 1 lb |
| 32 oz | 907.18474 g | 2 lb |
| 100 oz | 2834.9523125 g | 6.25 lb |
Avoirdupois Ounce, Troy Ounce and Fluid Ounce
This calculator uses the avoirdupois ounce. It is the regular mass ounce used for many packaged goods and general measurements. Its symbol is oz, and 16 oz make one avoirdupois pound.
| Unit | Exact relationship | Typical use |
|---|---|---|
| Avoirdupois ounce, oz | 28.349523125 g | General mass and packaged goods |
| Troy ounce, ozt | 31.1034768 g | Precious metals |
| Fluid ounce, fl oz | A volume unit, not a fixed gram mass | Liquids |
A troy ounce is exactly 2.753953675 g heavier than a regular ounce, about 9.7142857% more mass. A fluid ounce cannot be converted to grams without knowing the liquid's density and which fluid-ounce system applies.
Exact Gram, Ounce and Pound Relationships
The kilogram is the SI base unit of mass. A gram is exactly one-thousandth of a kilogram. The international avoirdupois pound equals exactly 0.45359237 kg, and one pound contains exactly 16 avoirdupois ounces.
Because the ounce-to-gram factor terminates, whole or finite-decimal ounce inputs produce terminating gram results. The reciprocal gram-to-ounce decimal usually repeats. “Exact factor” therefore does not mean every displayed decimal is exact.
When to Use Grams or Ounces
Grams are common on metric product labels, laboratory balances, nutrition records, shipping documents and recipes. Ounces remain common for general mass in U.S. customary settings. Converting between them helps when a package, scale or instruction uses a different unit from the one required by your record.
Read the original label before entering a number. If a food package says 12 oz, the value normally means avoirdupois mass. If a liquid container says 12 fl oz, it reports volume and does not belong in this converter. If a gold or silver listing says 12 ozt, it reports troy ounces and needs a precious-metals converter.
A conversion also preserves the nature of the source value. A stated net mass of 250 g converts to about 8.81849 oz, but the converted digits do not prove the package was measured to five decimal places. A recipe calling for 4 oz converts to exactly 113.3980925 g under the unit definition, while a kitchen scale might only let you measure 113 g or 113.4 g.
For repeated work, keep one unit as the calculation basis. Convert the original measurements once, retain guard digits internally, and round only the final reported quantity. This avoids error from switching back and forth between rounded gram and ounce values.
Exact Conversion, Rounding and Measurement Precision
The converter stores the entered decimal or fraction and the conversion factor as integer ratios. It does not pass the mass through a binary floating-point approximation. It rounds once, after conversion, using your decimal-place or significant-figure setting.
The default NIST-style ties-to-even rule affects an exact halfway case. If the retained digit is even, it stays unchanged. If it is odd, it increases. The optional ties-away rule is included for workflows that specify it. Most everyday values are not exact ties, so both rules give the same result.
Reporting precision still depends on the input. A kitchen scale reading of 100 g to the nearest gram should not be reported as though 3.52739619495804 oz were measured directly. Keep guard digits for later calculations, then report a sensible final precision.
Common Grams and Ounces Conversion Mistakes
- Using 31.1034768 g. That is a troy ounce, not the regular avoirdupois ounce used here.
- Treating fluid ounces as mass. Fluid ounces measure volume. A grams result needs density and a defined fluid-ounce system.
- Reversing the formula. Divide grams by 28.349523125. Multiply ounces by 28.349523125.
- Rounding the factor first. Multiplying by 0.035 or 0.0353 introduces avoidable error, especially for large quantities.
- Confusing oz and lb. Sixteen avoirdupois ounces make one pound. One ounce is 0.0625 lb.
- Adding unsupported certainty. An exact unit definition does not make an estimated or coarsely measured input more accurate.
Related Calculators
Frequently Asked Questions
How many ounces are in 1 gram?
One gram equals exactly 1600000/45359237 avoirdupois ounce, which is approximately 0.0352739619496 oz. The decimal repeats, so a finite decimal is rounded.
What is the formula for grams to ounces?
Divide grams by exactly 28.349523125. The equivalent exact formula is ounces = grams multiplied by 1600000/45359237.
How do I convert ounces to grams?
Multiply avoirdupois ounces by exactly 28.349523125. For example, 8 oz multiplied by 28.349523125 equals 226.796185 g.
Is 1 ounce exactly 28.349523125 grams?
Yes. One international avoirdupois ounce equals exactly 28.349523125 g. A rounded decimal in the reverse grams-to-ounces direction remains approximate.
How many ounces is 100 grams?
One hundred grams equals approximately 3.52739619496 oz. Rounded to two decimal places, it is 3.53 oz.
How many grams is 8 ounces?
Eight avoirdupois ounces multiplied by the exact factor equal 226.796185 g.
Are regular ounces and troy ounces the same?
No. A regular avoirdupois ounce is exactly 28.349523125 g, while a troy ounce is exactly 31.1034768 g. Precious-metal weights often use troy ounces.
Can fluid ounces be converted directly to grams?
No. A fluid ounce measures volume. Converting it to grams requires the substance's density and the correct U.S. or Imperial fluid-ounce definition.
Does oz mean ounce or fluid ounce?
The symbol oz means an ounce of mass in this calculator. Fluid ounce is written fl oz. Always check the label and context before converting.
Can I enter fractions or scientific notation?
Yes. The calculator accepts decimals, scientific notation, simple fractions and mixed numbers. Enter zero or a positive mass without a unit symbol or comma.
Method and Official Sources
The exact avoirdupois and troy-ounce factors follow NIST Handbook 44, 2026, Appendix C. Display rounding follows NIST SP 811, Appendix B. Gram and kilogram terminology follows NIST SI Units: Mass and the BIPM SI Brochure.
Measurement note: This tool converts entered mass values. It does not determine scale calibration, measurement uncertainty, package tolerances, density, precious-metal purity or whether an unidentified “ounce” means avoirdupois, troy or fluid ounce.