Liter or Litre? Which Spelling Is Correct?

Let’s say you want to buy some gasoline or maybe a bottle of water. And as it turns out, you’re also partial to the metric system. Should you consider your purchase in measurements of litres or liters? Which spelling is the correct one?

Let’s answer that.

What Are Litres and Liters?

We can begin by pointing out that both litre and liter are versions of a noun that refers to a metric unit of volume that is equal to 1,000 cubic centimeters, 1.75 pints, or roughly one-quarter of a gallon.

As you can likely conclude from this description, both are alternate spellings of the same word. That is, a liter is the same thing as a litre. It’s only the placement of the “r” and “e” that differs.

Of course, that doesn’t necessarily give you a resolute answer to the question. Although either spelling can technically be correct, there is one you will probably use far more often.

Should You Write Litres or Liters?

For the most part, liter is the preferred spelling in American English. If you’re within one of the 50 states—or writing for an audience that is—you should maintain the “-ers” spelling of liters. This is due mainly to the United States’ use of the imperial system of measurements. Only two other countries, Liberia and Myanmar, use the imperial system, and both now appear to be adopting the metric system.

Beyond the U.S., Liberia, and Myanmar, litre is the more common spelling and usage among English speakers around the globe.

In sum, if you are in the U.S., you will be correct if you spell your measurement with the American liter (which you also will see much less often than pints, quarts, and gallons). If you are in an English-speaking country outside of the U.S. except for Liberia or Myanmar, you will spell the measurement as litre.

Why Is Liter Spelled Two Ways in the First Place?

As with many small differences between American and international English, the real issue comes from the fact that the United States separated from England more than 200 years ago. In the generations since, our patterns of speaking, writing, and spelling have changed and shifted. This means certain words are pronounced, spelled, or even used differently across the Atlantic and Pacific oceans.

In the case of litres vs. liters, the words are still so close that you won’t likely cause any confusion or misunderstandings if you do prefer one spelling over the other. However, as pointed out, you will be aligned with American usage if you spell the word as liters.

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