Conversion calculators

Ounces To Grams Calculator

Updated Aug 1, 2026 By Jehan Wadia
Rate Formulas
Ounces (oz) → Grams (g)
Enter 0 to 999,999 ounces.
Type here to convert grams back into ounces.
Conversion Result
28.3495 g
Metric (grams)
28.3495 g
0 kg 28.3495 g
Imperial / US (ounces)
1.0000 oz
0 lb 1.0000 oz

How this was calculated:

1 oz × 28.349523125 = 28.3495 g
Step-by-Step Solution
Ounces to Grams Scale

Quick Select (oz)

Reference Conversion Table

Common Ounces to Grams Conversions — select a row to load that value into the calculator.
Ounces (oz) Grams (g) kg + g

Introduction

The Ounces to Grams Calculator changes ounces (oz) into grams (g) right away. Type a number, and you get the answer in a second. You can also flip it around and turn grams back into ounces with the Grams to Ounces Calculator.

One ounce equals 28.349523125 grams. That is the exact number this tool uses, so your answer is always correct. You pick how many decimal places you want, from 2 up to 8.

This helps a lot when you cook. Many recipes from the United States use ounces, but recipes from other places use grams. A kitchen scale often shows grams too. This calculator lets you switch between them fast, so your food comes out right — handy when you are working through a Recipe Cost Calculator or a Pizza Dough Calculator.

You can also enter weight as pounds plus ounces. That is handy for mail, baby weights, or bigger items. The tool shows your answer in a few ways: plain grams, kilograms plus grams, plain ounces, and pounds plus ounces. To move between metric and imperial mass in bulk, try the Kg To Lbs Calculator.

Every answer comes with steps that show the math. There is a chart, quick buttons for common sizes like 1 oz, 4 oz, and 8 oz, and a table of everyday conversions. Tap any row in the table to load that number.

How to use our Ounces to Grams Calculator

Type a weight in ounces and the calculator shows the same weight in grams. It also shows the answer in kilograms + grams and in pounds + ounces, plus the steps and a chart.

Ounces (oz): Type the number of ounces you want to change to grams. You can use decimals, like 2.5. The limit is 999,999 oz.

Decimal Places: Pick how many numbers show after the decimal point: 2, 4, 6, or 8. Use 2 for quick answers and 8 for exact work. If you need to control significant digits instead, the Sig Fig Calculator and Rounding Calculator can help.

Switch to lb + oz input: Click this button if your weight has pounds and ounces, like 1 lb 8 oz. Type the pounds in one box and the leftover ounces in the other. The tool adds them (1 lb = 16 oz) and then converts.

Grams (g): Type a gram value here to go the other way and get ounces. The tool flips to grams → ounces on its own.

Swap button (⇅): Click it to switch the direction between ounces → grams and grams → ounces.

Quick Select (oz): Tap a common ounce value, like 4, 8, or 16, to load it fast instead of typing.

Reference table: Click any row to send that ounce value into the calculator.

Convert, Clear, and Copy: Press Convert to update the answer, Clear to reset back to 1 oz, and Copy to save the result to your clipboard.

Ounces to Grams: What It Means

An ounce (oz) is a unit of weight used in the United States and other places that use the imperial system. A gram (g) is a unit of weight in the metric system, which most of the world uses. Converting ounces to grams lets you read a recipe, a food label, or a shipping weight in the units you know best. For length swaps, the Cm To Inches Calculator and Mm To Inches Calculator work the same way.

The Conversion Formula

One ounce equals exactly 28.349523125 grams. So:

  • Ounces to grams: grams = ounces × 28.349523125
  • Grams to ounces: ounces = grams × 0.0352739619495804 (this is 1 ÷ 28.349523125)

For quick math in your head, you can round and say 1 oz is about 28 g. Use the exact number when you need to be precise, like in baking or science.

Common Ounce to Gram Values

  • 1 oz = 28.35 g
  • 2 oz = 56.70 g
  • 4 oz = 113.40 g
  • 8 oz = 226.80 g
  • 16 oz (1 pound) = 453.59 g

Pounds and Ounces

There are 16 ounces in 1 pound (lb). If a weight is listed as 2 lb 4 oz, first change the pounds into ounces: 2 × 16 = 32, then add 4 to get 36 oz. Now multiply by 28.349523125 to get 1,020.58 g, which is about 1.02 kg. Kilograms are just grams divided by 1,000. If you need mass from a size and material instead, use the Density Calculator or the Mass Calculator.

Watch Out: Fluid Ounces Are Different

A fluid ounce (fl oz) measures volume, not weight. It tells you how much space a liquid takes up. An ounce measures how heavy something is. You cannot switch between fluid ounces and grams with one simple number, because different liquids have different weights. Water is close to 1 fl oz = 29.6 g, but oil, milk, and honey are not the same. For volume-only changes, use the Volume Conversion Calculator, and for liquid weight use the Specific Gravity Calculator.

Where You Will Use This

Cooks use it when a recipe from Europe lists grams but their scale shows ounces, and it pairs well with the Recipe Calorie Calculator. Shoppers use it to compare food labels alongside the Food Calorie Calculator. Mail and shipping often list package weight both ways, so check the Shipping Calculator, USPS Shipping Calculator, or Volumetric Weight Calculator when you post a parcel. Jewelry, coffee, spices, and gym supplements also come in both units — dieters often check grams with the Protein Calculator or Macro Calculator. Note that gold and silver use the troy ounce, which is heavier at 31.1035 grams, so this calculator does not apply to precious metals; use the Gold Price Calculator or Silver Calculator for those instead.


Formulas used

Ounces to grams
m_{\text{g}} = m_{\text{oz}} \times 28.349523125
Grams to ounces
m_{\text{oz}} = m_{\text{g}} \times 0.0352739619495804 = \frac{m_{\text{g}}}{28.349523125}
Pounds + ounces combined to total ounces
m_{\text{oz}} = lb \times 16 + oz
Grams expressed as kilograms + grams
kg = \left\lfloor \frac{m_{\text{g}}}{1000} \right\rfloor, \quad g_{\text{rem}} = m_{\text{g}} - 1000 \times kg
Ounces expressed as pounds + ounces
lb = \left\lfloor \frac{m_{\text{oz}}}{16} \right\rfloor, \quad oz_{\text{rem}} = m_{\text{oz}} - 16 \times lb

Frequently asked questions

How many grams are in half an ounce?

Half an ounce is 14.1748 g. Here is the math: 0.5 × 28.349523125 = 14.174761563 g. Most people round it to 14.17 g or just 14 g.

How many ounces is 100 grams?

100 grams is about 3.5274 oz. Type 100 in the Grams box and the tool flips direction on its own and shows the ounce answer.

Why is my answer a little different from the number on a food label?

Labels round. A 4 oz pack really weighs 113.398 g, but the label may just say 113 g or even 115 g. This calculator uses the exact factor, so it can be off by a fraction of a gram from a printed label. Both are fine.

Is 1 ounce 28 grams or 30 grams?

The true value is 28.349523125 g. Rounding to 28 g is close enough for cooking. Some nutrition labels use 30 g as a serving size, but that is a rounded serving, not a real ounce.

Is the US ounce the same as the UK ounce?

Yes. Both use the avoirdupois ounce, which is 28.349523125 g. So a recipe from the US and one from the UK mean the same ounce.

How do I convert ounces to kilograms?

Convert to grams first, then divide by 1,000. The calculator does this for you and shows the answer as kg + g in the results box. Example: 40 oz = 1,133.98 g = 1 kg 133.98 g.

How many grams is a stick of butter?

One US stick of butter is 4 oz, which is 113.4 g. Two sticks (8 oz) are 226.8 g, and four sticks (1 lb) are 453.59 g.

Does it matter if the item is dry or wet?

No. Ounces of weight and grams both measure how heavy something is, so flour, sugar, meat, and water all use the same factor. Only fluid ounces are different, because those measure volume.

How many decimal places should I pick?

Use what fits your job:

  • 2 — cooking, shipping, everyday use
  • 4 — baking and small amounts (this is the default)
  • 6 or 8 — lab work, science, or checking exact math

What does the Copy button copy?

It copies just the number, with no unit and no commas. That makes it easy to paste straight into a spreadsheet or another form.

Can I enter a negative weight?

No. Weight cannot be less than zero, so the tool treats negative entries as 0 and shows a short warning message.

What is the biggest number I can enter?

You can enter up to 999,999 oz, which is 28,349,523.125 g (about 28.3 tonnes). Anything higher is cut back to that limit.

How do I convert grams back into pounds and ounces?

Type your gram value in the Grams box. The result panel shows the answer in plain ounces and also as lb + oz. For example, 1,000 g = 2 lb 3.2740 oz.

How do I enter a baby's weight like 7 lb 6 oz?

Click Switch to lb + oz input. Put 7 in the pounds box and 6 in the ounces box. The tool adds them (7 × 16 + 6 = 118 oz) and gives 3,345.24 g, or 3 kg 345.24 g.

What is 3.5 oz in grams?

3.5 oz = 99.2233 g, or about 99 g. This is a common serving size for meat and fish.

Why is the chart a straight line?

Because the change is simple multiplying. Every extra ounce adds the same 28.349523125 g, so the line never bends. The orange dot marks your current answer.

Does the calculator round my input or only the answer?

It uses your full input in the math and only rounds what you see. So the steps and the result stay accurate even if you type a long decimal.