Weight Converter

Convert weight and mass between kilograms, grams, milligrams, micrograms, nanograms, picograms, femtograms, and attograms.

This calculator is useful when you need a quick unit check without working through each conversion factor by hand. Enter one value to compare every supported unit side by side.

Weight Converter

Enter a weight and choose its starting unit. The table converts the same amount from kilograms down to attograms.

WeightUse decimals or scientific notation.

From unit

Unit	Symbol	Equivalence	Value
kilogram	kg	1,000 g	1e-6
gram	g	1 g	0.001
milligram	mg	0.001 g	1
microgram	µg	1e-6 g	1000
nanogram	ng	10⁻⁹ g	1e6
picogram	pg	10⁻¹² g	1e9
femtogram	fg	10⁻¹⁵ g	1e12
attogram	ag	10⁻¹⁸ g	1e15

Method: convert the input to the base unit first, then convert from that base unit to each target unit. The base unit is gram (g).

Mass conversions across practical and laboratory scales

This converter helps when reading protocols, preparing samples, comparing instrument outputs, or moving between kilogram, gram, milligram, microgram, and smaller SI scales.

Example

Enter 1 milligram to see that it equals 1,000 micrograms or 1e6 nanograms.