Density and Mass
lbtodr
Convert pounds (avoirdupois) (lb) to drams (avoirdupois) (dr).
Factor1 lb = 256 dr
Converter
lb
Accepts numbers or expressions, e.g. 150 + 14.7
Result
dr
Rendered to 6 significant figures.
Formula
Formula
dr = lb × 256
Multiply any value in pounds (avoirdupois) by 256 to obtain the value in drams (avoirdupois).
Worked example
Convert 1 lb to dr.
- 01Start with 1 lb.
- 02Multiply by the conversion factor: 1 × 256 = 256 dr.
Result1 lb = 256 dr
Conversion table
| lb | dr |
|---|---|
| 1 | 256 |
| 2 | 512 |
| 5 | 1280 |
| 10 | 2560 |
| 20 | 5120 |
| 50 | 12800 |
| 100 | 25600 |
| 200 | 51200 |
| 500 | 1.2800e+5 |
| 1000 | 2.5600e+5 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from lb to dr?
1 lb equals 256 dr. To convert, multiply the value in pounds (avoirdupois) by 256.
How do I convert 1 lb to dr?
1 lb = 256 dr. For any value, multiply by 256.
How do I convert dr back to lb?
Divide by the same factor — or equivalently, multiply by 0.00390625. So 1 dr = 0.00390625 lb.
When would I need to convert pound (avoirdupois) to dram (avoirdupois)?
Mass conversions appear in material balances, reagent dosing, and reconciling vendor specifications across imperial/metric systems.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).