How to Express Numbers, Times, and Measures in Indonesian?

Decimal Place and Thousands Separator

Great Britain, Australia, New Zealand, and the United States (along with some former British and American colonies) are among the few countries globally that use a full-stop (period) to indicate the decimal place. In contrast, most other countries opt for a comma.

Similarly, while many English-speaking countries use a comma to separate thousands, many other countries use a period instead.

Indonesia follows the European system:

Alternatively, you can express it as: satu kilogram dan lima ratus gram.

Widespread, though unofficial, is the use of setengah (one half) and seperempat (one quarter) in Indonesian: satu setengah kilometer (one and a half kilometres)

Time

The modern 24-hour clock is the standard for timekeeping, where the day runs from midnight to midnight, divided into 24 hours. This convention is followed by most countries globally. While many English-speaking countries still maintain the 12-hour clock system with a.m. (ante meridian) and p.m. (post meridian), official announcements, such as train timetables, often use the 24-hour clock.

Indonesia adopts the 24-hour clock convention. However, in casual conversation, the 12-hour clock convention may also be employed. Nonetheless, a.m. and p.m. are never added. To avoid confusion, you may append pagi (morning), siang (around noon), sore (afternoon), or malam (night).

In line with the European convention, the hour is separated from the minutes by a titik (full-stop or period) rather than a titik dua (colon):

In spoken language, you can also say: Acaranya mulai jam satu lewat tiga puluh menit siang, or, even more commonly: Acaranya mulai jam setengah dua.

Measures

While most of the world adopts the International System of Units—the metric system—the United States has its own system based on the old British Imperial System, using inches and pounds, with temperature measured in Fahrenheit.

The US and Liberia are the only remaining countries globally that still use this outdated system. The UK has embraced the metric system, but with imperial units still in widespread use among the public. However, this doesn’t provide much help for Americans, as a British mile or gallon is not the same as the US mile or gallon.

So, is Indonesia fully metric?

Indonesian Tons and Ounces

Yes, Indonesia fully adheres to the metric system. In 1923, it adopted the metric system, becoming compulsory since 1938, during the time when Indonesia was still a Dutch colony. The Netherlands, adopting the metric system much earlier in 1820, still retains remnants of the old system.

Many European countries, though long metricised, have retained some remnant of the old system. In Germany for instances, it is common to use pounds, but only in colloquial speech, as this is not an official unit of measurement. Yet, the German pound (called Pfund) has been metricised and weighs 500 gr. In the Netherlands, the Dutch ounce, called ons, was also metricised. One ons is equal to one hundred grams.

Indonesia has borrowed this custom from the Dutch. So, if you’re an American sharing a smoothie recipe with your Indonesian friend, calling for one ounce of sugar (28 grams), your Indonesian friend might be upset for suggesting a recipe that turns out to be excessively sweet.

One ton, a US customary unit of weight, is equal to 907 kilograms, whereas the British tonne measures 1016 kg. As in most European countries, the Indonesian ton is metricised and weighs 1000 kg.

The US is also among very few countries that still use British Thermal Units (BTU). This is a unit of measurement that shows just how much energy your air conditioner uses to remove heat from your home within an hour. Indonesians will not understand you if you tell them that your air conditioner has 18,000 BTU. You must use kw/h instead.

Body Weight and Height

In some English-speaking countries, particularly among the older generation, people refer to their body weight in stones or pounds and their body height in feet and inches.

What if you tell an Indonesian that you are six foot five inches tall? Will they be impressed? No, they will not be impressed simply because they don’t understand you! Tell them that you are 196 cm tall, and they will be impressed.

But can’t you quickly use your cell phone to convert your body height? No, you’re out of luck since online converters only understand if you enter that you are six point something feet tall. So you have to use multiple steps to convert 6 foot 5 inches into six point something, and only then can you convert your height into centimetres.

So, forget about Fahrenheit, Miles, Yards, Pounds, Stones, and Feet, as nobody will understand you.