Gallon (US) to Teaspoon (UK) Converter

Volume Converter

40 units available

Decimals:

From

To

639.493774

1 gal = 639.493774 tsp (UK)

Formula:

tsp (UK) = gal × 639.4937737954

With your value: 1 gal = 639.4937738 tsp (UK)

How big is that?

Everyday references on a logarithmic scale, all expressed in gallon (us) so you can sanity-check the result.

Milk carton (1/3.8e+3 your value)0.000264 gal

Kitchen bucket (1/3.8e+2 your value)0.00264 gal

Car fuel tank (1/76 your value)0.0132 gal

Bathtub (1/19 your value)0.0528 gal

Hot tub (1/2.5 your value)0.396 gal

Your value1.00 gal

Other Gallon (US) to Teaspoon (UK) conversions

2 gal to tsp (UK)3 gal to tsp (UK)4 gal to tsp (UK)5 gal to tsp (UK)6 gal to tsp (UK)7 gal to tsp (UK)8 gal to tsp (UK)

Gallon (US) to Teaspoon (UK) Conversion Table

Gallon (US) (gal)	Teaspoon (UK) (tsp (UK))
0.5	319.746887
1	639.493774
2	1,278.987548
5	3,197.468869
10	6,394.937738
15	9,592.406607
20	12,789.875476
25	15,987.344345
50	31,974.68869
100	63,949.37738
250	159,873.443449
500	319,746.886898
1000	639,493.773795

Teaspoon (UK) to Gallon (US) Conversion Table

Teaspoon (UK) (tsp (UK))	Gallon (US) (gal)
0.5	0.000782
1	0.001564
2	0.003127
5	0.007819
10	0.015637
15	0.023456
20	0.031275
25	0.039093
50	0.078187
100	0.156374
250	0.390934
500	0.781868
1000	1.563737

Where these values come from

Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.

Gallon (US) (gal)

Volume

Exact conversion

The US liquid gallon is exactly 231 cubic inches = 3.785 411 784 L.

Source: NIST Handbook 44, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

Teaspoon (UK) (tsp (UK))

Volume

Exact conversion

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

Source: NIST Special Publication 811, Guide for the Use of the International System of Units

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

How to Convert Gallon (US) to Teaspoon (UK)

To convert from Gallon (US) (gal) to Teaspoon (UK) (tsp (UK)), multiply the value by 639.4937737954.

Formula: tsp (UK) = gal × 639.4937737954

Reverse: gal = tsp (UK) × 0.0015637369

Step-by-Step Example

Start with your value in Gallon (US). For example: 5 gal
Multiply by the conversion factor: 5 x 639.4937737954
The result is: 3,197.468869 tsp (UK)

About Gallon (US)

The US gallon equals approximately 3.785 liters and is the standard unit for fuel and large liquid volumes in the United States.

Fun Fact: The US gallon is about 20% smaller than the imperial (UK) gallon.

Common uses: fuel (US), beverages, swimming pools.

About Teaspoon (UK)

The teaspoon (uk) (tsp (UK)) is a unit of volume and capacity. One teaspoon (uk) equals 0.005919388021 litres. UnitConvertLab converts it against every other volume unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: volume calculations, engineering and science, education.

Frequently Asked Questions

How many Teaspoon (UK) are in 1 Gallon (US)?

There are exactly 639.4937737954 Teaspoon (UK) in 1 Gallon (US). This means the conversion factor from Gallon (US) to Teaspoon (UK) is 639.4937737954.

What is the formula to convert Gallon (US) to Teaspoon (UK)?

The formula to convert Gallon (US) to Teaspoon (UK) is: tsp (UK) = gal × 639.4937737954. For example, to convert 10 Gallon (US) to Teaspoon (UK), you would multiply 10 by 639.4937737954.

What is a Gallon (US)?