“i.e.” and “e.g.”: How To Use the Most CONFUSING Abbreviations

These two abbreviations get mixed up constantly. Most of the time, people use “i.e.” incorrectly when they mean “e.g.” But sometimes it’s the other way around.

A big part of the problem is likely that both “i.e.” and “e.g.” are not English abbreviations but LATIN. When folks don’t even know what the letters stand for, it’s no wonder they get confused! So let’s dive into these little tricksters and figure out which one’s which and how to use them correctly.

A quick word to the wise before we get started: Not everyone likes these abbreviations. Some people prefer to avoid them altogether, and that’s totally fine! There are English equivalents for both of them (I’ll include those in the following sections) that you can use instead. The abbreviations “i.e.” and “e.g.” are just short and handy, plus they look kinda fancy when you use them correctly.

e.g. = “for example”

The abbreviation “e.g.” is short for exempli gratia, meaning “for example.” This should be used when you’re listing examples.

My mom wanted to plant flowers (e.g., roses, tulips, and daisies) all along the front path.

IN OTHER WORDS: My mom wanted to plant flowers (for example, roses, tulips, and daisies) all along the front path.

The abbreviation “e.g.” introduces one or more examples that illustrate something you’ve stated:

I was asked to list an emergency contact (e.g., a spouse) on the form.

Note that “e.g.” should only be used when you’re listing one or a few examples of many; this abbreviation implies that there are more examples that aren’t listed. In the example above, there are other people who could be listed as an emergency contact; a spouse is just one option of many.

If you’re writing a comprehensive list, do not use “e.g.” You might use “including” (or nothing at all) instead:

The class was asked to paint their name tags one of the primary colors (e.g., red, yellow, or blue).

There are only three primary colors and we listed all of them, so “e.g.” is not correct.

The class was asked to paint their name tags one of the primary colors (red, yellow, or blue).

The list of soups (e.g., broccoli cheddar, chicken noodle, and tomato) was short.

In this example, we listed all of the soups on the menu, so we don’t need “e.g.”

The list of soups (including broccoli cheddar, chicken noodle, and tomato) was short.

What About “ex.”?

The prefix “ex” means “former” (as in ex-boyfriend or ex-president) and it should not be used as an abbreviation for “example.” If you don’t want to use “e.g.,” you can write out “for example.”

i.e. = “that is” or “in other words”

The abbreviation “i.e.” is short for id est, meaning “that is.” This should be used when you’re rewording or clarifying a statement. You can remember this by thinking of “i.e.” as being short for “in essence.”

The restaurant was over capacity (i.e., there were too many people inside).

Only one country (i.e., the United States) has hosted the Winter Olympics four times.

When you’re using “i.e.,” you’re giving another option for how to word something you’ve said. You might want to do this if your writing includes a lot of technical terms or if there’s any room for misunderstanding.

To Sum Up

Use “e.g.” to list examples, and use “i.e.” to reword a term or statement.

The local movie theater is showing some exciting films right now (e.g., The Avengers, Kung Fu Panda, and The Godfather).

In this situation, there are several exciting films being shown at the theater and I’m listing a few of them (but not all of them).

The local movie theater is showing the newest Marvel movie (i.e., Avengers Endgame) right now.

In this situation, there is only ONE newest Marvel movie, and I’m clarifying which one it is.

If you’re not sure which abbreviation is correct, try substituting “in other words” or “for example.” If “in other words” makes sense, you need “i.e.” If “for example” makes sense, use “e.g.”

4 Rules About Using “i.e.” and “e.g.”

Rule #1: Always Include a Period after Each Letter

Because both “i.e.” and “e.g.” are abbreviations, a period is required after BOTH letters in each abbreviation.

Giant dog breeds (eg, Great Danes and St. Bernards) can sometimes make great family pets.

Giant dog breeds (eg., Great Danes and St. Bernards) can sometimes make great family pets.

Giant dog breeds (e.g., Great Danes and St. Bernards) can sometimes make great family pets.

Rule #2: Always Include a Comma after the Second Period

These abbreviations have more punctuation marks than they do letters, so it’s understandable that people want to leave something out, but it is essential to include a comma after “e.g.” and “i.e.”

In fact, just think of the abbreviations as being spelled “i.e.,” and “e.g.,” (with the commas included) because they’ll be required every single time you use them.

You should also always use a comma BEFORE these abbreviations unless they’re enclosed in parentheses.

She called her neighbor fatuous, i.e. stupid, after hearing his latest daredevil attempt.

This one is missing the comma after “i.e.”

She called her neighbor fatuous i.e. stupid, after hearing his latest daredevil attempt.

This one is missing two commas: one before “i.e.” and one after it.

She called her neighbor fatuous, i.e., stupid, after hearing his latest daredevil attempt.

This has all the commas it needs!

She called her neighbor fatuous (i.e. stupid) after hearing his latest daredevil attempt.

We don’t need commas surrounding the “i.e.” statement because the parentheses are there. However, we still need one after “i.e.”

She called her neighbor fatuous (i.e., stupid) after hearing his latest daredevil attempt.

I’ve used “i.e.” as an example here, but the same rule applies to “e.g.”

Rule #3: Both are ALWAYS Lowercase.

I’ve carefully avoided starting any sentence in this post with “i.e” or “e.g.” because I know that both letters in each abbreviation should always be lowercase, and I don’t want to start a sentence with a lowercase letter. For this same reason (and just because of the nature of these abbreviations), you should never start a sentence with “i.e.” or “e.g.”

Rule #4: Never Italicize “i.e.” or “e.g.”

This might seem like a funny rule for a few reasons. First, why would you randomly italicize these abbreviations? Well, words in languages other than English are usually italicized in English writing. Since “i.e.” and “e.g.” are abbreviations for Latin phrases (id est and exempli gratia), it seems like they should be italicized. After all, when we spell out those abbreviations, we DO italicize the words.

So…then why do we NOT italicize the abbreviations?

It just comes down to how long we’ve been using the abbreviations. They’ve been around for long enough that they’re now integrated into the English language. This actually happens pretty frequently: English tends to “steal” words from other languages (like “tortilla” and “karaoke”) and just claim them as its own.

Bonus Abbreviation: etc.

If you’re hungry for more Latin abbreviations, here’s a quick guide to using “etc.”!

The abbreviation “etc.” is Latin for et cetera, which means “and the others” or “and the rest.” It’s used to show that a list continues on and you’re just stating a few examples.

Arrange the documents in chronological order: January, February, March, etc.

TRANSLATION: Arrange the reports in chronological order: January, February, March, and so on

Because “etc.” stands for “and the rest,” you should NOT put “and” in front of it.

The hardware store sells basic tools (hammers, screwdrivers, saws, and etc.).

The hardware store sells basic tools (hammers, screwdrivers, saws, etc.).

Unlike “i.e.” and “e.g.,” “etc.” should NOT have a comma after it unless it’s require by the surrounding text:

The map was clearly from a previous decade (it lacked some streets, shops, neighborhoods, etc., that had since been built).

The map was clearly from a previous decade (it lacked some streets, shops, neighborhoods, etc. that had since been built).

If you have any questions about these abbreviations, drop them in the comments and I’ll find you an answer!

Sources:

• The Chicago Manual of Style. 17th ed. Chicago, IL: The University of Chicago Press, 2017.
• Ebbitt, D. R., and W. R. Ebbitt. Index to English. 8th ed. New York: Oxford University Press, 1990.
• “E.g. vs. I.e.—What’s the Difference?” Grammarly, June 10, 2020. https://www.grammarly.com/blog/acronyms-abbreviations/know-your-latin-i-e-vs-e-g/#:~:text=If%20you%20want%20your%20examples,associated%20with%20them%2C%20in%20parentheses.
• Einsohn, Amy. The Copyeditor’s Handbook. 3rd ed. Berkeley and Los Angeles, California: Univ of California Pr, 2011.
• Merriam-Webster. Merriam-Webster’s Dictionary of English Usage. 14th ed. Taunton, MA: QuadGraphics, 2016.