Volume · Unit Converter

Convert Cubic Decimeter to US Gallon

Convert cubic decimeters to us gallons instantly. 1 cubic decimeter = 0.2641720524 us gallon — use the live calculator, the exact formula, a conversion table and worked examples. Also check the US Gallon to Cubic Decimeter 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

Metric / SI

Cubic Decimeter

What is a cubic decimeter?

A cubic decimeter is the volume of a cube one decimeter on a side, exactly equal to one liter (0.001 m³).

Origin of the cubic decimeter

Derived from the decimeter; in 1964 the CGPM defined the liter as exactly one cubic decimeter.

Where it is used

Common in chemistry and engineering as an exact synonym for the liter.

When and where it was developed

CGPM, 1964.

US Customary (Liquid)

US Gallon

What is a us gallon?

The US liquid gallon is defined as exactly 231 cubic inches (3.785411784 liters).

Origin of the us gallon

Based on the English wine gallon of 231 cubic inches, retained by the US after 1824.

Where it is used

The primary US unit for fuel, milk and large beverage containers.

When and where it was developed

English wine gallon; US since 1824.

Cubic Decimeter to US Gallon conversion formula

The relationship between cubic decimeters and us gallons:

1 dm³ = 0.2641720524 gal
1 gal = 3.785411784 dm³

To convert cubic decimeters to us gallons, multiply the value in cubic decimeters by 0.2641720524. To reverse, multiply us gallons by 3.785411784.

How to use this converter

Type a value into the calculator. The result in us gallons 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 Gallon to Cubic Decimeter converter for the reverse direction.

Step-by-step: convert cubic decimeters to us gallons

  1. Write down the value in cubic decimeters (dm³).
  2. Multiply that value by the factor 0.2641720524.
  3. The product is the equivalent value in us gallons (gal).
  4. To reverse, multiply the us gallon value by 3.785411784.

Worked examples

Example 1 — Convert 1 dm³ to gal:
1 × 0.2641720524 = 0.2641720524 gal

Example 2 — Convert 100 dm³ to gal:
100 × 0.2641720524 = 26.4172052358 gal

Real-world example — Ruler-scale measurements

A 30-cubic decimeter school ruler converts cleanly to us gallons — useful when buying a desk accessory from a retailer whose product specs use a different unit.

30 dm³ × 0.2641720524 = 7.9251615707 gal

Real-world example — Hardware-scale dimensions

A 10-cubic decimeter fastener or component is about as long as a thumbnail. Mechanics and DIY enthusiasts convert between cubic decimeters and us gallons daily when mixing metric and imperial tools.

10 dm³ × 0.2641720524 = 2.6417205236 gal

Real-world example — Postcard and small-object dimensions

A postcard is about 5 cubic decimeters wide. Converting to us gallons is essential for international postal addressing forms that ask for dimensions in different units across countries.

5 dm³ × 0.2641720524 = 1.3208602618 gal

Cubic Decimeter to US Gallon conversion table

Standard reference values for converting cubic decimeters to us gallons:

Cubic Decimeter [dm³]US Gallon [gal]
0.010.0026417205
0.10.0264172052
10.2641720524
20.5283441047
30.7925161571
41.0566882094
51.3208602618
102.6417205236
205.2834410472
307.9251615707
4010.5668820943
5013.2086026179
10026.4172052358
500132.0860261791
1000264.1720523581

Frequently asked questions

How many us gallons is 1 cubic decimeter?
1 cubic decimeter equals 0.2641720524 us gallon.
How do I convert cubic decimeters to us gallons?
Multiply the value in cubic decimeters by 0.2641720524 to get us gallons.
How do I convert us gallons back to cubic decimeters?
Multiply the value in us gallons by 3.785411784, or use the US Gallon to Cubic Decimeter converter.
How many us gallons is 100 cubic decimeters?
100 cubic decimeters equals 26.4172052358 us gallons, because 100 × 0.2641720524 = 26.4172052358.

Convert Cubic Decimeter to other volume units

Show all Cubic Decimeter conversions

Sources & references

Conversion factor (1 dm³ = 0.2641720524 gal) verified against the following authoritative sources:

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