Volume · Unit Converter

Convert Imperial Gallon to US Fluid Dram

Convert imperial gallons to us fluid drams instantly. 1 imperial gallon = 1229.772723717 us fluid dram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the US Fluid Dram to Imperial Gallon converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Jaya Christiyan K G, Ph.D.
Volume category 2 min read Published Last reviewed Updated

Units explained

Imperial (UK)

Imperial Gallon

What is a imperial gallon?

The imperial gallon is defined as exactly 4.54609 liters.

Origin of the imperial gallon

Set by the British Weights and Measures Act of 1824 as the volume of 10 lb of water.

Where it is used

Used for fuel and beverages in the UK and Commonwealth.

When and where it was developed

UK, 1824.

US Customary (Liquid)

US Fluid Dram

What is a us fluid dram?

A US fluid dram is 1/8 of a US fluid ounce (3.6967 mL).

Origin of the us fluid dram

An apothecaries' subdivision of the fluid ounce.

Where it is used

Historical pharmacy unit, now rare.

When and where it was developed

Apothecaries' system.

Imperial Gallon to US Fluid Dram conversion formula

The relationship between imperial gallons and us fluid drams:

1 gal = 1229.772723717 fl dr
1 fl dr = 0.0008131584 gal

To convert imperial gallons to us fluid drams, multiply the value in imperial gallons by 1229.772723717. To reverse, multiply us fluid drams by 0.0008131584.

How to use this converter

Type a value into the calculator. The result in us fluid drams updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the US Fluid Dram to Imperial Gallon converter for the reverse direction.

Step-by-step: convert imperial gallons to us fluid drams

  1. Write down the value in imperial gallons (gal).
  2. Multiply that value by the factor 1229.772723717.
  3. The product is the equivalent value in us fluid drams (fl dr).
  4. To reverse, multiply the us fluid dram value by 0.0008131584.

Worked examples

Example 1 — Convert 1 gal to fl dr:
1 × 1229.772723717 = 1229.772723717 fl dr

Example 2 — Convert 100 gal to fl dr:
100 × 1229.772723717 = 122977.2723716971 fl dr

Real-world example — Adjacent metric sub-units

One imperial gallon equals 1,000 us fluid drams. Engineers move between these scales constantly: PCB feature sizes in the larger unit, wire-bond diameters in the smaller.

1 gal × 1229.772723717 = 1229.772723717 fl dr

Real-world example — Adjacent small-scale precision

One imperial gallon equals 1,000 us fluid drams — the standard sub-millimeter precision conversion that materials engineers use whenever they switch between bulk material thickness specs (larger unit) and surface-finish characteristics (smaller unit).

1 gal × 1229.772723717 = 1229.772723717 fl dr

Imperial Gallon to US Fluid Dram conversion table

Standard reference values for converting imperial gallons to us fluid drams:

Imperial Gallon [gal]US Fluid Dram [fl dr]
0.0112.2977272372
0.1122.9772723717
11229.772723717
22459.5454474339
33689.3181711509
44919.0908948679
56148.8636185849
1012297.7272371697
2024595.4544743394
3036893.1817115091
4049190.9089486789
5061488.6361858486
100122977.2723716971
500614886.3618584856
10001229772.7237169712

Frequently asked questions

How many us fluid drams is 1 imperial gallon?
1 imperial gallon equals 1229.772723717 us fluid dram.
How do I convert imperial gallons to us fluid drams?
Multiply the value in imperial gallons by 1229.772723717 to get us fluid drams.
How do I convert us fluid drams back to imperial gallons?
Multiply the value in us fluid drams by 0.0008131584, or use the US Fluid Dram to Imperial Gallon converter.
How many us fluid drams is 100 imperial gallons?
100 imperial gallons equals 122977.2723716971 us fluid drams, because 100 × 1229.772723717 = 122977.2723716971.

Convert Imperial Gallon to other volume units

Show all Imperial Gallon conversions
Metric / SI (15 units)
US Customary (Liquid) (15 units)
US Customary (Dry) (5 units)
Imperial (UK) (13 units)
Cubic (length-derived) (4 units)
Cooking / Culinary (5 units)
Industrial / Specialized (6 units)

Sources & references

Conversion factor (1 gal = 1229.772723717 fl dr) verified against the following authoritative sources:

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