Daltons to Pounds (Da to lb)
1 dalton equals 3.660861996×10⁻²⁷ pounds (rounded).
How to convert daltons to pounds
To convert daltons to pounds, multiply the number of daltons by 3.660861996×10⁻²⁷. The factor is rounded to 10 significant digits. To go the other way, multiply pounds by 2.731597097×10²⁶ (rounded).
pounds = daltons × 3.660861996×10⁻²⁷
Example: 10 daltons = 3.660861996×10⁻²⁶ pounds.
Approximate value. Standards for the dalton varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.
About these units
Dalton (Da)
About 1.66054×10⁻²⁷ kg, one twelfth of the mass of a carbon-12 atom. Used for atoms, molecules and proteins.
Chemists and biologists quote the mass of a protein as so many kilodaltons, a habit that goes back to John Dalton, who in 1803 suggested taking the lightest atom, hydrogen, as the natural yardstick for atomic weights. The unit itself took other forms for a long time. Around 1903 chemists settled on one sixteenth of an oxygen atom, and in 1960 and 1961 the physics and chemistry unions replaced that with a carbon-12 standard, calling it the unified atomic mass unit with the symbol u.
The name dalton, symbol Da, was proposed by IUPAC in 1993 and endorsed by IUPAP in 2005. It is the same unit as u and is defined as one twelfth of the mass of a free carbon-12 atom at rest in its ground state. The 2022 CODATA value, listed by NIST and in Wikipedia, is 1.66053906892 x 10^-27 kg, with a small uncertainty in the final digits. A helium-4 atom weighs about 4.0026 Da, and the giant protein titin about 3 to 3.7 MDa. The BIPM accepts the unit for use with the SI, and the 2019 redefinition of the kilogram left its definition unchanged.
1 dalton = 1.660539069×10⁻²⁷ kilograms (approximately).
Sources: Wikipedia: Dalton (unit); NIST CODATA: unified atomic mass unit
Pound (lb)
Exactly 0.45359237 kg, divided into 16 ounces. The standard unit of weight in the US and common in the UK.
Why is pound abbreviated lb? The answer is Roman. The English word comes from the Latin libra pondo, roughly the weight measured in libra, and the symbol keeps the first word. The Roman libra was divided into 12 unciae. The avoirdupois pound of 16 ounces came into general use around 1300 and was initially equal to 6,992 troy grains; under Elizabeth I it was redefined as 7,000 grains. The UK's Weights and Measures Act 1878 set the imperial standard pound as a platinum cylinder, and the troy pound was abolished for trade the following year.
Today the pound is defined from the kilogram. The International Yard and Pound Agreement of 1959 fixed it at exactly 0.45359237 kg, and the UK's Weights and Measures Act 1963 wrote the same figure into law. Pounds remain the everyday unit for body weight, groceries and shipping in the United States and are widely used in the UK. The word also survives in odd places: a six-pounder cannon was named for the weight of its shot, not its own.
1 pound = 0.45359237 kilograms (exactly).
Sources: Wikipedia: Pound (mass); NIST Guide to the SI, Appendix B.8 (mass conversions)
Related conversions
- Pounds to daltons (reverse)
- Daltons to kilograms
- Daltons to grams
- Daltons to metric tons
- Daltons to ounces
- Kilograms to pounds
- Grams to pounds
- Metric tons to pounds
- Ounces to pounds
- Milligrams to pounds
- Micrograms to pounds
- Carats to pounds
- Stone to pounds
- Short tons to pounds
- Long tons to pounds
- Troy ounces to pounds
- Earth masses to pounds
See all weight & mass units.