Imperial gallon to Imperial teaspoon

One imperial gallon is defined as exactly 4.54609 liters — approximately 20% more than the US liquid gallon (3.785 L).

The UK switched fuel sales to liters in the 1990s. However, miles per gallon (imperial) remains the legal unit for car fuel economy on new vehicle labels. Road speed is in mph and distances are in miles, so imperial gallons remain embedded in UK motoring.

UK MPG uses the imperial gallon (4.546 L); US MPG uses the US gallon (3.785 L). Multiply UK MPG by 0.832 to get US MPG. A car rated 40 UK MPG ≈ 33 US MPG.

There are exactly 8 imperial pints in one imperial gallon. Each imperial pint is 568 mL, compared to 473 mL for a US pint.

Canada officially metricated in the 1970s and fuel is sold in liters. However, some older Canadians and certain agricultural contexts still reference imperial gallons informally. Canadian and UK imperial gallons are identical (4.54609 L).

One imperial teaspoon equals approximately 5.919 mL — slightly larger than the US teaspoon (4.929 mL) and the metric teaspoon (5 mL).

An imperial teaspoon is approximately 5.92 mL; a metric teaspoon is exactly 5 mL. The metric teaspoon is now standard in UK cooking, medicine, and pharmacology.

The imperial teaspoon is obsolete in modern UK, Australian, and Canadian cooking, which all use the 5 mL metric teaspoon. It may appear in cookbooks published before the 1970s metrication period.

A culinary pinch — the amount you can hold between thumb and forefinger — is roughly 0.3–0.5 mL, or about 1/16 of a teaspoon. Professional recipe developers have measured this and found surprising consistency across people: the human fingertip geometry constrains how much fine powder you can grip. A "dash" (liquid) is about 0.6 mL, and a "smidgen" is half a pinch (~0.15 mL). These folksy terms survive in recipes because they map to real, repeatable volumes — within the tolerance that salt and spice measurements actually require.

The WHO recommended the 5 mL metric teaspoon for medication dosing in the 1970s to eliminate ambiguity between imperial (5.92 mL), US (4.93 mL), and other teaspoon sizes. A calibrated 5 mL oral syringe is now the recommended tool for all liquid medicines.