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Sources and Accuracy
Weight and mass conversions use kilogram as the reference unit. Common factors include 1 pound = 0.45359237 kilogram and 1 ounce = 0.028349523125 kilogram.
Displayed results are rounded for readability. The calculator keeps enough precision for everyday use and switches to scientific notation for very large or very small values. Last reviewed: 2026-05-21.
About These Units
grain [gr]
Definition
The grain (gr) is a weight unit used to express measurements in this converter.
History
This unit is included because it appears in practical measurement systems, technical references, product specifications, or everyday conversion needs.
Current use
Use grain when comparing weight values, checking specifications, converting between systems, or preparing quick estimates.
ounce [oz]
Definition
The ounce is an avoirdupois mass unit equal to 28.349523125 grams.
History
The avoirdupois ounce became the standard ounce for general weight measurement.
Current use
Ounces are used for food packages, recipes, postal weights, consumer goods, and small shipments.