What is this converter?
Converts mass between metric units (milligram to tonne) and imperial units (ounce, pound). All conversions pass through the kilogram, the SI base unit of mass.
Use it when:
- A recipe, shipping label, or specification uses a mass unit you do not work in.
- You are comparing product weights quoted in different systems.
- You need to convert a bulk quantity between tonnes and pounds.
Intended for: Cooks, shippers, traders, and anyone comparing masses across measurement systems.
How is this calculated?
- Each supported unit is defined by a fixed conversion factor relative to one base unit for the quantity (for example, the metre for length).
- The value you enter is first converted from the source unit into that base unit by multiplying by the source unit's factor.
- The base value is then converted into the target unit by dividing by the target unit's factor.
- Because both factors are exact constants, the conversion is a single deterministic multiplication and division — the same input always produces the same output.
Example
Converting 70 kilograms to pounds.
- 1 pound is exactly 0.45359237 kilograms.
- 70 ÷ 0.45359237 ≈ 154.3236.
Result: 70 kilograms ≈ 154.32 pounds.
Frequently asked questions
Is this mass or weight?
Strictly it converts mass. In everyday use the two are treated interchangeably because weight is proportional to mass at a constant gravitational field, which is the assumption everyday measurements make.
Which tonne is used?
The metric tonne of exactly 1,000 kilograms. The US short ton (907.18 kg) and the UK long ton (1,016.05 kg) are different units and are not in the list.
Is the ounce here the same as a fluid ounce?
No. This is the avoirdupois ounce, a unit of mass (28.3495 g). A fluid ounce measures volume and belongs in the volume converter.
Assumptions
What this converter takes as given:
- Conversion factors are the internationally standardised definitions of each unit, not regional or historical variants.
- The value you enter is treated as an exact quantity — no measurement uncertainty is carried through the conversion.
- Results are rounded only for display; the underlying arithmetic uses full precision.
Limitations
What this converter cannot know or does not model:
- The converter does not know the precision of your original measurement, so it cannot report significant figures for you.
- Units that share a name but differ by region or era (for example, different definitions of a gallon or a ton) are offered only in the variants listed in the unit menu.
- Very large or very small magnitudes are subject to the limits of double-precision floating-point arithmetic.