Convert Grain to Slug
Convert grains to slugs instantly. 1 grain = 4.440135e-6 slug — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Slug to Grain converter for the reverse conversion.
Units explained
Grain
The grain (gr) equals 1/7000 of an avoirdupois pound, about 64.8 milligrams.
Based on the nominal mass of a single barley grain.
Ammunition and bullet mass, archery, and historical pharmacy.
Standardized through the English avoirdupois system and retained in 1959.
Slug
The slug is the mass that accelerates at 1 ft/s^2 under a force of one pound-force, about 14.59 kg.
Coined in the early 20th century for the British gravitational (engineering) system.
US and British engineering dynamics.
Introduced in the British gravitational system of units.
Grain to Slug conversion formula
The relationship between grains and slugs:
To convert grains to slugs, multiply the value in grains by 4.440135e-6. To reverse, multiply slugs by 225218.3746514216.
How to use this converter
Type a value into the calculator. The result in slugs updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Slug to Grain converter for the reverse direction.
Step-by-step: convert grains to slugs
- Write down the value in grains (gr).
- Multiply that value by the factor 4.440135e-6.
- The product is the equivalent value in slugs (slug).
- To reverse, multiply the slug value by 225218.3746514216.
Worked examples
Example 1 — Convert 1 gr to slug:
1 × 4.440135e-6 = 4.440135e-6 slug
Example 2 — Convert 100 gr to slug:
100 × 4.440135e-6 = 0.0004440135 slug
Real-world example — Paper and film thicknesses
At the thickness of office paper (roughly 3 grains), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.
3 gr × 4.440135e-6 = 1.332041e-5 slug
Real-world example — Plastic-film thickness alternates
A 150-grain plastic film converts cleanly to slugs — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.
150 gr × 4.440135e-6 = 0.0006660203 slug
Real-world example — Hair-width scale measurements
A 70-grain measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like slugs for direct comparison across supplier datasheets.
70 gr × 4.440135e-6 = 0.0003108095 slug
Grain to Slug conversion table
Standard reference values for converting grains to slugs:
| Grain [gr] | Slug [slug] |
|---|---|
| 0.01 | 4.440135e-8 |
| 0.1 | 4.440135e-7 |
| 1 | 4.440135e-6 |
| 2 | 8.88027e-6 |
| 3 | 1.332041e-5 |
| 4 | 1.776054e-5 |
| 5 | 2.220068e-5 |
| 10 | 4.440135e-5 |
| 20 | 8.88027e-5 |
| 30 | 0.0001332041 |
| 40 | 0.0001776054 |
| 50 | 0.0002220068 |
| 100 | 0.0004440135 |
| 500 | 0.0022200675 |
| 1000 | 0.0044401351 |
Frequently asked questions
How many slugs is 1 grain?
How do I convert grains to slugs?
How do I convert slugs back to grains?
How many slugs is 100 grains?
Popular weight unit conversions
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)
Sources & references
Conversion factor (1 gr = 4.440135e-6 slug) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.