Mass & Weight Converter

Convert mass units (kg, g, lb, oz, t) and weight/force units (N, kN, lbf, kgf) using precise factors. Includes explanation of mass vs weight so users don’t mix them up.

Mass conversion

Reference: 1 kg = 2.20462262 lb = 35.27396195 oz = 0.1574730444 st. 1 metric tonne (t) = 1000 kg.

Kilogram (kg):1
Gram (g):1000
Pound (lb):2.204623
Ounce (oz):35.27396
Stone (st):0.15747
Metric tonne (t):0.001

Mass vs Weight

Mass is intrinsic and doesn’t change with location. It’s measured in kilograms, grams, pounds, ounces, stones, and tons. Weight is a force: the pull of gravity on that mass. On Earth, weight can be estimated by multiplying mass by standard gravity 9.80665 m/s².

Core formulas

Mass (kg) → Pounds (lb): lb = kg × 2.20462262

Pounds (lb) → kg: kg = lb ÷ 2.20462262

Weight (N) → kgf: kgf = N ÷ 9.80665

kgf → N: N = kgf × 9.80665

Common use cases

  • Lab / chemistry: convert mg ↔ g ↔ kg quickly.
  • Shipping / logistics: convert between kg and lb/st/short ton.
  • Engineering / structural: work in N or kN, but report in kgf to non-technical stakeholders.

FAQ

1. Can I enter a very small mass like micrograms?

Yes, µg is supported. The converter internally uses kilograms as a base, so precision is preserved.

2. Why do you show both US short ton and UK long ton?

Because 1 US short ton = 2000 lb (≈ 907.18474 kg), while 1 UK long ton = 2240 lb (≈ 1016.0469 kg). Mixing them causes invoicing errors.

3. How to get weight on the Moon?

Weight = mass × Moon gravity (1.62 m/s²). Our main weight tab assumes Earth gravity; for other planets, multiply manually by the local gravitational acceleration.