Weight and Mass Converter

Weight and Mass Converter

Convert everyday weight labels and technical mass units through kilograms. The page supports metric mass, avoirdupois pounds and ounces, stones, short tons, long tons, grains, and slugs with a full comparison table.

Base unit

kilogram

Supported units

12

Includes

metric + avoirdupois

No sign-upFormula shownPrint-friendly

Live converter

Weight and mass inputs

Enter a value, choose the source and target units, then inspect the full table for related physical units.

lb

Converted result

68.0388555 kg

Input

150 lb

Output unit

kg

Base method

kilograms

Mass in every supported unit

UnitConverted valueUnit name
ug6.803886 x 10^+10Micrograms
mg68,038,855.5Milligrams
g68,038.8555Grams
kg68.0388555Kilograms
t0.0680388555Metric tonnes
gr1,050,000Grains
oz2,400Ounces avoirdupois
lb150Pounds avoirdupois
st10.7142857143Stones
ton (US)0.075Short tons
ton (UK)0.0669642857Long tons
slug4.6621434641Slugs
What Can You Create?

Convert body weight, packages, recipes, and technical mass

Everyday weight labels

Move between pounds, ounces, kilograms, grams, and stones for health, travel, fitness, and consumer labels.

Shipping and inventory

Compare kilograms, pounds, short tons, long tons, and metric tonnes for logistics and material estimates.

Science and engineering

Convert small metric masses, grains, and slugs when a problem mixes measurement traditions.

Formula

Weight and mass conversion formula

The converter treats unit labels as mass values and normalizes every input to kilograms before scaling to the target unit.

Working formulas

Base conversion

kilograms = value x kilograms per source unit

The input is first converted into the SI base unit for mass.

Target value

target value = kilograms / kilograms per target unit

The kilogram value is divided by the target unit factor.

Exact pound relationship

1 lb = 0.45359237 kg

The avoirdupois pound factor anchors pounds, ounces, and stones.

Symbols

kilograms per unit - mass factor
The factor used to normalize the source or target unit.
target value - converted mass
The displayed result after scaling from kilograms.
Why Users Love This Tool

Why this mass converter is practical

Clear unit systems

  • Metric mass and avoirdupois units are shown together without hiding the kilogram base.
  • Short tons and long tons are separate entries, reducing ambiguity in logistics and material notes.
  • The result table makes it easy to compare nearby units without retyping the source value.

Audit-friendly precision

  • The formula section shows the kilogram route used by the converter.
  • Pound and ounce conversions use the exact international pound relationship.
  • Small and large results remain readable with compact formatting and scientific notation when needed.
Perfect For

Useful when weight labels cross systems

Health and fitness

Convert body weight and equipment loads between pounds, kilograms, stones, and ounces.

Shipping teams

Compare package and freight masses across kilograms, pounds, short tons, and metric tonnes.

Students and labs

Convert grams, milligrams, kilograms, grains, and slugs for classroom and technical examples.

How It Works

How it works in three quick steps.

1

Enter the value

Type the weight or mass from a label, recipe, shipment, classroom problem, or specification.

2

Select units

Choose the source unit and the target unit. The result updates immediately and the table shows every supported unit.

3

Audit the kilogram route

Use the formula section to confirm the value was normalized to kilograms before being scaled into the target unit.

Download & Print

Keep mass conversions easy to reuse

Copy selected result

Copy the source and target unit result with labels for documents, assignments, and shipment notes.

Print the table

Print the full mass table when a task needs repeated lookups across metric and customary units.

Reference the formula

Use the kilogram formula notes to explain which conversion factor produced the result.

About This Tool

About this weight and mass converter

Weight and mass conversion is common in everyday work, but the labels can be imprecise. A scale reading in pounds or kilograms is usually treated as weight in casual language, while the conversion factor is a mass relationship. This page uses kilograms as the base so metric, avoirdupois, and engineering mass units can be compared consistently.

The converter separates units that are often confused, especially short tons and long tons. It also includes small metric units and grains for cases where a problem or product specification reaches beyond pounds and kilograms. The full table lets users see the surrounding unit scale without repeating the same input.

The formula section is visible because physical unit conversions should be auditable. A copied result is more useful when another person can see that the value was normalized to kilograms and then converted into the target unit.

Keep building

Explore more unit converters

Converters