Grams to ounces converter
Turn a metric mass into US ounces with the exact definition: 100 g is 3.527396194958 oz, because one ounce is exactly 28.349523125 grams. Handy for food labels, recipe cards and parcel forms. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Grams
- 100
- Result
- 3.527396195 oz
- Converted
- 3.527396195
- Ounces
- 3.527396195
- From unit
- g
A grams-to-ounces converter turns a metric mass into the avoirdupois ounce used on United States food labels, postal forms, kitchen scales, and science worksheets.
Why grams and ounces meet at exactly 28.349523125
Grams and ounces remain the two everyday mass units that people type into search boxes when a kitchen scale, a food label, or a shipping form switches systems. The gram is the SI unit of mass; the avoirdupois ounce is the customary unit used in the United States for groceries, parcels, and many school worksheets.
Their relationship is not a survey estimate: the international yard and pound agreement of 1959 fixed one pound at exactly 0.45359237 kilogram, and the avoirdupois pound is defined as sixteen ounces, so one ounce is exactly 28.349523125 grams. This converter applies that definition in one direction only: ounces equals grams divided by 28.349523125. It does not convert fluid ounces of volume, troy ounces of precious metal, or apothecary ounces; those share a name with different sizes and would mislead searchers who typed grams to ounces for grocery or shipping weight.
Zero grams maps cleanly to zero ounces. Non-finite values such as NaN or Infinity also fail.
Practical tips, checks, and related searches
Prefer sending bare numbers when you control the client; string numbers are accepted only when they match a strict finite numeric pattern without units, thousand separators, or currency symbols. Round-trip sanity checks are easy: convert 28.349523125 grams and confirm you receive exactly one ounce after rounding, convert one hundred grams and confirm the published twelve-decimal ounce value, or convert zero and confirm zero. When teaching, show that multiplying the published ounces by 28.349523125 recovers the original grams within the same twelve-decimal rounding used for published fields.
Prefer this capability when the input is already in grams and you only need ounces.
What you can do with it
Kitchen labels and recipe scaling
Convert metric ingredient masses from grams into ounces for US packaging labels, smaller batch sizes, and recipe cards that quote avoirdupois weight.
Shipping and postal forms
Turn gram-based scale readings into ounces for carrier forms, rate tables, and warehouse manifests that still require the customary unit.
FAQ
What formula converts grams to ounces?
Ounces = grams ÷ 28.349523125. One avoirdupois ounce is defined as exactly 28.349523125 grams (one sixteenth of the international pound 0.45359237 kg).
Does this convert fluid ounces or troy ounces?
No. It converts grams to avoirdupois mass ounces only. Fluid ounces measure volume; troy ounces are a different mass unit used for precious metals.
What happens if grams is negative or not a finite number?
Negative masses and non-finite values (NaN, Infinity, or non-numeric strings) are rejected and are not billed.
Is the grams to ounces converter free?
The browser tool is free and runs locally.
Why is an ounce exactly 28.349523125 grams?
Because the 1959 international yard and pound agreement fixed the pound at exactly 0.45359237 kilogram, and an avoirdupois pound is 16 ounces. Dividing gives an ounce of exactly 28.349523125 grams, with nothing estimated.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/conv/g-to-oz \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"grams":100}'const res = await fetch("https://api.kit.forhosting.com/conv/g-to-oz", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"grams": 100
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/g-to-oz",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"grams": 100
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/g-to-oz", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"grams":100}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"grams":100}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/g-to-oz", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"grams": 100
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.g_to_oz",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
Negative masses and non-finite values fail with invalid_input instead of inventing a number.
Why grams and ounces meet at exactly 28.349523125
Negative masses are rejected with invalid_input because a physical mass cannot be negative on this landing.
How to call the API and what comes back
The value must be non-negative and finite. Send a JSON body with one required finite number field named grams. Aliases g, gram, value, mass, weight, and grams_value are accepted so SDK clients and form posts can use the name that fits the product. On success the response echoes rounded grams, sets ounces, result, and converted to the same rounded ounce magnitude, unit to the token oz, from_unit to g and to_unit to oz, factor to the reciprocal of 28.349523125, grams_per_ounce to 28.349523125, formula to the string ounces equals grams divided by 28.349523125, message to a short English summary, and steps to an ordered array of substitution lines that show the international definition. Failed validation, including missing fields, non-finite numbers, negative grams, bare plus or minus signs, or non-numeric strings, returns invalid_input and is never charged. Pricing is a flat $0.002 per successful request with unit item.
Practical tips, checks, and related searches
Stay inside the IEEE double range so the division cannot overflow into a non-finite result the solver must reject. This landing targets people searching for g to oz, grams to ounces, or an exact 28.349523125 gram-per-ounce calculator; it is not a general multi-unit mass hub, not an ounces-to-grams primary form, not a cooking density converter, and not a fluid-ounce volume converter. Failed tasks that return invalid_input do not consume prepaid balance, which keeps exploratory scripts cheap when learners deliberately omit grams or pass text.
Integration use cases
Homework and unit-test fixtures
Students and engineers convert classroom gram masses to ounces and pin golden JSON so browser and API arithmetic never drift.
Technical questions
Is the factor 28.349523125 exact?
Yes. From the 1959 international pound (0.45359237 kg exactly) and the avoirdupois split of sixteen ounces per pound, 1 oz = 28.349523125 g with no remaining uncertainty.