Travel Units Converter

The conversions travel actually throws at you

Cross a border and the numbers change. The forecast is suddenly in Celsius, the speed-limit signs in kilometres, the baggage scale in kilograms and the petrol pump in litres. None of it is hard, but doing it in your head at the airport scale or the motorway on-ramp is exactly when mistakes happen. This converter covers the handful of units that travel keeps throwing at you \u2014 distance, temperature, weight, volume, speed and fuel economy \u2014 with the common values spelled out so you can sanity-check at a glance.

Luggage weight: kilograms and pounds

The two figures you\u2019ll see most are 23 kg (50 lb), the usual checked-bag allowance, and 32 kg (70 lb), a frequent absolute maximum a single bag can weigh for handler safety. Carry-on limits are lower and vary widely \u2014 often 7\u201310 kg. If your home scale reads in the other system, convert before you get to the airport, where going over means repacking at the desk or paying an excess-bag fee. Pair this with the carry-on size checker to make sure the bag fits as well as weighs in.

Liquids and the 100 ml rule

Cabin-baggage liquids are capped at 100 ml (about 3.4 US fl oz) per container, with all containers fitting inside one transparent resealable bag of roughly a litre. The rule is written in millilitres, so US travellers buying \u201c3.4 oz\u201d travel bottles are right at the line. Note the limit is per container, not per total volume, and a half-full 200 ml bottle still isn\u2019t allowed \u2014 it\u2019s the labelled size that counts. (Some airports are rolling out scanners that relax this; until it\u2019s posted at your departure airport, assume 100 ml.)

Driving abroad: speed and fuel

Renting a car means reading speeds in the local unit and judging fuel use on the fly. For speed, a few anchors go a long way: 50 km/h \u2248 31 mph (city), 100 km/h \u2248 62 mph, 120 km/h \u2248 75 mph(motorway). For fuel, remember the figure can be in L/100km (lower is better) or mpg(higher is better) \u2014 and that a US gallon (3.79 L) is about 20% smaller than a UK gallon (4.55 L), so \u201c40 mpg\u201d means quite different things on each side of the Atlantic. The converter keeps US and UK mpg separate so you don\u2019t mix them up.

Temperature: packing for the weather

When the forecast switches systems, pack by these anchors: 0 \u00b0C = 32 \u00b0F (freezing), 20 \u00b0C = 68 \u00b0F (mild), 30 \u00b0C = 86 \u00b0F (hot). A quick mental trick: double the Celsius value and add 30 for a rough Fahrenheit estimate (25 \u00b0C \u2192 \u201880, actually 77 \u2014 close enough to pack). For anything precise, use the converter.

A word on clothing and shoe sizes

One set of conversions we deliberately don\u2019t put numbers on here is clothing and shoe sizes. While US/UK/EU systems have broad equivalents, real sizing varies so much by brand, cut and country that a single chart would mislead more than it helps. The reliable approach is to check the specific retailer\u2019s own size guide, and where possible go by measurements (foot length in cm, chest/waist in cm or inches) rather than a label \u2014 those you can convert here.