Instant · Precise · Universal
34 units available
6 categories total
To convert Da to kg: multiply by 1.6605390666 × 10⁻²⁷. 1 kDa = 1,000 Da.
1 Da = 1 u = 1.6605390666 × 10⁻²⁷ kg. Proteins range from ~5 kDa to >1,000 kDa.
For example, 1 Dalton (Da) = 1.693279e-28 Kilogram-force second²/meter (kgf·s²/m).
| Dalton (Da) | Kilogram-force second²/meter (kgf·s²/m) |
|---|---|
| 0.1 | 1.693279e-29 |
| 0.5 | 8.466393e-29 |
| 1 | 1.693279e-28 |
| 2 | 3.386557e-28 |
| 5 | 8.466393e-28 |
| 10 | 1.693279e-27 |
| 25 | 4.233197e-27 |
| 50 | 8.466393e-27 |
| 100 | 1.693279e-26 |
| 500 | 8.466393e-26 |
| 1000 | 1.693279e-25 |
The dalton is a unit of mass equal to one unified atomic mass unit (1/12 of a carbon-12 atom), approximately 1.661 × 10⁻²⁷ kg.
1 Da = 1 u = 1.6605390666 × 10⁻²⁷ kg. Proteins range from ~5 kDa to >1,000 kDa.
To convert Da to kg: multiply by 1.6605390666 × 10⁻²⁷. 1 kDa = 1,000 Da.
Protein molecular weights (hemoglobin ≈ 64.5 kDa), DNA fragment sizing, and antibody characterization.
Titin, the largest known protein, has a molecular weight of about 3,800 kDa (3.8 MDa). The average protein is ~40–50 kDa.
The dalton and u are identical — they're just preferred in different fields (Da in biology, u in chemistry/physics).
If a paper says a protein is '50 kDa,' that's 50,000 atomic mass units — about 50,000 hydrogen atoms' worth of mass.
The kilogram-force second squared per meter is an engineering unit of mass in the gravitational metric system, equal to about 9.807 kg.
1 kgf·s²/m = 9.80665 kg (exactly), based on standard gravity g₀ = 9.80665 m/s².
To convert to kilograms: multiply by 9.80665.
Historical engineering calculations where force was in kgf and F=ma needed consistent units.
This unit is the metric equivalent of the slug (imperial system). Just as 1 lb-force accelerates 1 slug at 1 ft/s², 1 kgf accelerates this unit at 1 m/s².
Mixing up mass (kg) and weight (kgf) in the gravitational system. SI removed this confusion by using newtons for force.
This unit exists because the gravitational system used kgf (force) as base, so a derived mass unit was needed for F=ma to work.



© 2026 UntangleTools. All Rights Reserved.