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oz to Grams Converter

ConvertersWeight & Mass
Grams — g

One avoirdupois ounce equals 28.349523125 grams exactly, so multiply ounces by 28.3495 to get grams. An 8 oz block of cheese weighs about 226.8 g, and a 16 oz pound is 453.59 g. The factor follows from the 1959 definition of the pound as 0.45359237 kg.

Ounces to Grams conversion table

ozg
128.3495
256.699
5141.748
10283.495
20566.99
25708.738
501,417.48
1002,834.95
2507,087.38
50014,174.8
1,00028,349.5

About this tool

American recipes, food labels and parcel scales weigh in ounces, while European cookbooks, nutrition panels and most lab balances read in grams. This converter turns an ounce figure into grams as you type and shows the multiplication behind it, along with a table of common amounts. It handles the avoirdupois ounce used for food and everyday goods. It does not cover the troy ounce used for gold and silver, which is about 10 % heavier at 31.1035 g, and it does not convert fluid ounces, which measure volume rather than weight.

How to use it

  1. Type the weight in ounces

    Enter the number of ounces in the oz field. Fractions as decimals work, such as 0.25 for a quarter ounce.

  2. Read the grams

    The gram value and the multiplication used appear while you type, with a table of nearby amounts below.

  3. Swap or share

    Press Swap to go from grams back to ounces, or Share to send a link that reopens the same number.

Examples

A single ounce

Ounces
1

Result Grams: 28.3495

  1. 1 oz × 28.3495 = 28.3495 g

One avoirdupois ounce is 1/16 of the international pound, which works out to just over 28.35 grams.

Half an ounce of spice

Ounces
0.5

Result Grams: 14.1748

  1. 0.5 oz × 28.3495 = 14.1748 g

Recipes that call for half an ounce of a spice or yeast need about 14.17 grams on a kitchen scale.

A one-pound pack

Ounces
16

Result Grams: 453.5924

  1. 16 oz × 28.3495 = 453.5924 g

Sixteen ounces make one pound, so a 16 oz pack of pasta or butter holds 453.6 grams.

How it is calculated

g = oz × 28.349523125

oz
mass in avoirdupois ounces (1/16 of a pound)
g
mass in grams

Since the 1959 international yard and pound agreement, one pound is exactly 0.45359237 kilograms. The avoirdupois ounce is one sixteenth of that pound, so it is 453.59237 ÷ 16 = 28.349523125 grams, an exact value with no rounding. Converting is therefore a single multiplication with no offset.

When not to use it

  • Do not use it for precious metals priced per troy ounce, which is 31.1035 g rather than 28.3495 g.
  • Do not use it for fluid ounces on a drinks label, because those measure volume and need the liquid's density to become grams.

Common mistakes

  • Rounding the factor to 28 g loses about 1.2 %, which adds up to 5.6 g on a one-pound recipe.
  • Treating a fluid ounce of flour as a weight ounce: a cup of flour is 8 fl oz but only about 4.25 oz by weight.

Frequently asked questions

How many grams are in one ounce exactly?

One avoirdupois ounce is exactly 28.349523125 grams. Kitchen work usually rounds that to 28.35 g, and nutrition labels in the United States often use 28 g per ounce as a serving shorthand.

What is the difference between a troy ounce and a regular ounce?

A troy ounce, used for gold, silver and platinum, is 31.1034768 g. The regular avoirdupois ounce used for food is 28.3495 g, so a troy ounce is roughly 9.7 % heavier.

How many ounces are in 100 grams?

100 grams is about 3.527 ounces. That is 100 divided by 28.3495, which is what the swap direction of this converter calculates.

Is a fluid ounce the same weight as an ounce?

Only for water and liquids of similar density. A US fluid ounce of water weighs about 29.6 g, close to one weight ounce, but oil, honey and flour differ noticeably.

How many grams is a quarter pound?

A quarter pound is 4 ounces, which is 4 × 28.349523125 = 113.398 g. Enter 4 in the ounce field to see the full working.

Cite this tool

Using this tool in an assignment, article or report? Copy a citation, or a link for your website.

APA

Tools Directory Editorial Team. (2026, October 24). oz to Grams Converter. Tools Directory. Retrieved October 26, 2026, from https://tools.milunir.com/converters/weight-mass/oz-to-grams-converter/

MLA

Tools Directory Editorial Team. “oz to Grams Converter.” Tools Directory, 24 Oct. 2026, https://tools.milunir.com/converters/weight-mass/oz-to-grams-converter/. Accessed 26 Oct. 2026.

Chicago

Tools Directory Editorial Team. “oz to Grams Converter.” Tools Directory. Last modified October 24, 2026. Accessed October 26, 2026. https://tools.milunir.com/converters/weight-mass/oz-to-grams-converter/.

Link<a href="https://tools.milunir.com/converters/weight-mass/oz-to-grams-converter/">oz to Grams Converter – Tools Directory</a>