Mass and Weight · Unit Converter

Convert Grain to Pound

Convert grains to pounds instantly. 1 grain = 0.0001428571 pound — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Pound to Grain converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Avoirdupois

Grain

What is a grain?

The grain (gr) equals 1/7000 of an avoirdupois pound, about 64.8 milligrams.

Origin of the grain

Based on the nominal mass of a single barley grain.

Where it is used

Ammunition and bullet mass, archery, and historical pharmacy.

When and where it was developed

Standardized through the English avoirdupois system and retained in 1959.

Avoirdupois

Pound

What is a pound?

The pound (lb) is a unit of mass equal to exactly 0.45359237 kilogram.

Origin of the pound

From Latin 'libra pondo' (a pound by weight); the symbol lb comes from 'libra'.

Where it is used

The primary weight unit in the United States and informally in the UK.

When and where it was developed

The international avoirdupois pound was fixed in the 1959 yard-and-pound agreement.

Grain to Pound conversion formula

The relationship between grains and pounds:

1 gr = 0.0001428571 lb
1 lb = 7000.0010802653 gr

To convert grains to pounds, multiply the value in grains by 0.0001428571. To reverse, multiply pounds by 7000.0010802653.

How to use this converter

Type a value into the calculator. The result in pounds updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Pound to Grain converter for the reverse direction.

Step-by-step: convert grains to pounds

  1. Write down the value in grains (gr).
  2. Multiply that value by the factor 0.0001428571.
  3. The product is the equivalent value in pounds (lb).
  4. To reverse, multiply the pound value by 7000.0010802653.

Worked examples

Example 1 — Convert 1 gr to lb:
1 × 0.0001428571 = 0.0001428571 lb

Example 2 — Convert 100 gr to lb:
100 × 0.0001428571 = 0.0142857121 lb

Real-world example — From microscopic to macroscopic

A million grains equals exactly one pound. This kind of conversion appears in microfluidics, where total channel length is given in pounds but feature widths are in grains.

1000000 gr × 0.0001428571 = 142.8571208109 lb

Real-world example — Macro-scale buildup

A million grains equals exactly one pound — the conversion that bridges microscale features and macroscale objects in microfluidic, biomedical, and semiconductor packaging design.

1000000 gr × 0.0001428571 = 142.8571208109 lb

Real-world example — Quarter-meter measurement reference

A 250,000-grain length equals 0.25 pounds — useful for comparing supply-chain spec sheets where some lengths are quoted in the smaller unit and some in the larger.

250000 gr × 0.0001428571 = 35.7142802027 lb

Grain to Pound conversion table

Standard reference values for converting grains to pounds:

Grain [gr]Pound [lb]
0.011.428571e-6
0.11.428571e-5
10.0001428571
20.0002857142
30.0004285714
40.0005714285
50.0007142856
100.0014285712
200.0028571424
300.0042857136
400.0057142848
500.007142856
1000.0142857121
5000.0714285604
10000.1428571208

Frequently asked questions

How many pounds is 1 grain?
1 grain equals 0.0001428571 pound.
How do I convert grains to pounds?
Multiply the value in grains by 0.0001428571 to get pounds.
How do I convert pounds back to grains?
Multiply the value in pounds by 7000.0010802653, or use the Pound to Grain converter.
How many pounds is 100 grains?
100 grains equals 0.0142857121 pounds, because 100 × 0.0001428571 = 0.0142857121.

Convert Grain to other weight units

Show all Grain conversions
Metric / SI (18 units)
Avoirdupois (14 units)
Troy & Apothecary (10 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Force / Engineering (5 units)

Sources & references

Conversion factor (1 gr = 0.0001428571 lb) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.