Convert US Gallon to Tun
Convert us gallons to tuns instantly. 1 us gallon = 0.003968254 tun — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Tun to US Gallon converter for the reverse conversion.
Units explained
US Gallon
The US liquid gallon is defined as exactly 231 cubic inches (3.785411784 liters).
Based on the English wine gallon of 231 cubic inches, retained by the US after 1824.
The primary US unit for fuel, milk and large beverage containers.
English wine gallon; US since 1824.
Tun
A tun is 252 US gallons (953.92 L), the largest traditional liquid cask.
From Old English/French for a large barrel; the basis of 'tonnage'.
Historical for wine and the origin of ship tonnage.
Medieval cask system.
US Gallon to Tun conversion formula
The relationship between us gallons and tuns:
To convert us gallons to tuns, multiply the value in us gallons by 0.003968254. To reverse, multiply tuns by 252.
How to use this converter
Type a value into the calculator. The result in tuns updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Tun to US Gallon converter for the reverse direction.
Step-by-step: convert us gallons to tuns
- Write down the value in us gallons (gal).
- Multiply that value by the factor 0.003968254.
- The product is the equivalent value in tuns (tun).
- To reverse, multiply the tun value by 252.
Worked examples
Example 1 — Convert 1 gal to tun:
1 × 0.003968254 = 0.003968254 tun
Example 2 — Convert 100 gal to tun:
100 × 0.003968254 = 0.3968253968 tun
Real-world example — Body height conversion
You enter your height as 180 us gallons into an international job or visa application. The form then asks for the same value in tuns — converting between these adjacent units is one of the most-used length conversions globally.
180 gal × 0.003968254 = 0.7142857143 tun
Real-world example — Furniture and large objects
A 72-us gallon piece of furniture converts to a value in tuns that's easier to mentally compare with room dimensions. This is the typical workflow when shopping internationally and product specs use a different unit than your room measurements.
72 gal × 0.003968254 = 0.2857142857 tun
Real-world example — Children's height milestones
A 150-us gallon-tall child measures a value in tuns that's commonly used for theme-park ride height requirements when travelling between countries that use different measurement units.
150 gal × 0.003968254 = 0.5952380952 tun
US Gallon to Tun conversion table
Standard reference values for converting us gallons to tuns:
| US Gallon [gal] | Tun [tun] |
|---|---|
| 0.01 | 3.968254e-5 |
| 0.1 | 0.0003968254 |
| 1 | 0.003968254 |
| 2 | 0.0079365079 |
| 3 | 0.0119047619 |
| 4 | 0.0158730159 |
| 5 | 0.0198412698 |
| 10 | 0.0396825397 |
| 20 | 0.0793650794 |
| 30 | 0.119047619 |
| 40 | 0.1587301587 |
| 50 | 0.1984126984 |
| 100 | 0.3968253968 |
| 500 | 1.9841269841 |
| 1000 | 3.9682539683 |
Frequently asked questions
How many tuns is 1 us gallon?
How do I convert us gallons to tuns?
How do I convert tuns back to us gallons?
How many tuns is 100 us gallons?
Popular volume unit conversions
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Metric / SI (15 units)
US Customary (Liquid) (14 units)
US Customary (Dry) (5 units)
Imperial (UK) (14 units)
Cubic (length-derived) (4 units)
Cooking / Culinary (5 units)
Sources & references
Conversion factor (1 gal = 0.003968254 tun) 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 Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.