Making Sense of American Units: Pounds, Fahrenheit, and Gallons

When you first arrive in the U.S., the "lb" on your grocery receipt, the "°F" on the weather app, and the "gal" at the gas station can all feel like a foreign language. Rather than memorizing conversion formulas, the fastest way to adapt is to lock in a handful of real-life reference points.

Weight: Pounds (lb) and Ounces (oz)

One pound is about 454 grams, and one ounce is roughly 28 grams. At the grocery store, think of 1 lb as a little less than half a kilogram — about the size of two palm-sized cuts of meat. When you need a quick mental calculation, use kg × 2.2 = lbs. So if you weigh 65 kg, that's about 143 lbs. Baby weights and medical records often mix the two (e.g., "7 lbs 4 oz"), so remember there are 16 oz in a pound. At stores like Costco or H Mart, package weights are always in lbs, so this reference will come in handy constantly.

Temperature: Fahrenheit (°F)

The exact formula is (°F − 32) ÷ 1.8 = °C, but for daily life, just memorize these benchmarks:

• 32°F → 0°C — freezing point. Watch for icy roads.
• 50°F → 10°C — time for a light jacket.
• 72°F → 22°C — what Americans call "perfect weather."
• 95°F → 35°C — serious summer heat.

In the beginning, just Google "85°F in Celsius" whenever you're unsure. After a few weeks, the numbers will start to feel natural on their own.

Volume: Gallons (gal) and Fluid Ounces (fl oz)

One gallon equals about 3.78 liters. To build a feel for it at the gas station, keep in mind that a typical sedan holds 12–15 gallons (roughly 45–57 liters). At the grocery store, a one-gallon jug of milk (usually $3–$5) is about the same as four standard 1-liter cartons. For drinks, a Starbucks Grande is 16 fl oz — about 473 mL. In recipes, 1 cup = 8 fl oz ≈ 240 mL, which is useful to know when you're switching between Korean and American cookbooks.