About and approximately: ぐらい

～ぐらい・～くらい ~gurai, ~kurai About; approximately

ぐらい (or くらい) after a number means "about": 十分ぐらい, about ten minutes. It comes after the number, where English puts "about" before it.

Level: JLPT N5, beginner
Type: Counting
English links: approximation, time expressions, how long / how much / how many

What it means

ぐらい means "about" or "roughly". It goes after an amount: a number with its counter, or a length of time. 十分ぐらい is about ten minutes. 三十人ぐらい is about thirty people.

ぐらい and くらい mean the same thing. Both are correct, and you will hear both. どのぐらい (or どれぐらい) asks "how long" or "how much": 日本に来て、どのぐらいですか means "How long have you been in Japan?"

For a point in time on the clock, many textbooks teach ごろ instead: 三時ごろ, at about three. In speech you will also hear 三時ぐらい, but ごろ is the safe choice. The English point to remember is word order. Japanese puts "about" after the number. English puts it before.

How to build it

Pattern	How it works
Number + counter + ぐらい number + counter + gurai	二時間ぐらい, 五人ぐらい. About two hours, about five people.
どのぐらい / どれぐらい dono gurai / dore gurai	How long? How much? How many?
Time + ごろ time + goro	三時ごろ. At about three. Use ごろ for a point on the clock.

Examples

駅まで歩いて十分ぐらいです。 eki made aruite juppun gurai desu. It's about ten minutes on foot to the station.
毎日二時間ぐらい勉強します。 mainichi nijikan gurai benkyou shimasu. I study for about two hours every day.
このクラスには学生が三十人ぐらいいます。 kono kurasu ni wa gakusei ga sanjuunin gurai imasu. There are about thirty students in this class.
日本に来て、どのぐらいですか。 nihon ni kite, dono gurai desu ka. How long have you been in Japan?
三時ごろ来てください。 sanji goro kite kudasai. Please come at about three.

How English says it

English puts "about" or "around" before the number: about ten minutes, around thirty people. "Approximately" is the formal one. In speech you also hear "or so" after the number: ten minutes or so. And "three-ish" for times.

With lengths of time, English often needs "for": "I study for about two hours." And the question word changes with the thing you ask about: "how long" for time, "how many" for things you count, "how much" for money or amounts.

Why it can make English hard

ぐらい comes after the number, so some students put "about" at the end in English too: "two hours about".
どのぐらい covers time, number and amount. English needs "how long", "how many" or "how much", and students have to choose.
Japanese 二時間勉強します has no word for "for", so the English "for two hours" often goes missing.

Mistakes you will hear

I study two hours about every day. I study for about two hours every day. "About" goes before the number, and time length often needs "for".
How long time does it take? How long does it take? どのぐらい時間 translated word by word. "How long" already means time.
I came to Japan about three years. I have been in Japan for about three years. (or: I came to Japan about three years ago.) For a length of time up to now, use the present perfect with "for".

In the classroom

Play "Guess the number". Hold up a jar of sweets or a stack of handouts. Students guess with "about": "I think there are about fifty."
Ask "How long does it take you to get to school?" around the class. Students answer "About twenty minutes by bike." Then they ask each other.
Write ぐらい after a number and "about" before the same number on the board, with an arrow. One picture shows the word order change.

Practice

Try each one, then open it to check.

1. Fill the gap: 家から学校まで三十分＿＿＿かかります。 (It takes about thirty minutes from home to school.)

Answer: ぐらい (or くらい)

ぐらい after an amount of time means "about".
2. Translate: このクラスには学生が三十人ぐらいいます。

Answer: There are about thirty students in this class.

"About" goes before the number in English.
3. A student writes "I slept six hours about." Fix it.

Answer: I slept for about six hours.

"About" goes before the number, and a length of time often takes "for".
4. Which is better for a time on the clock: 七時ぐらい or 七時ごろ?

Answer: 七時ごろ

ごろ is the standard word for a point in time. ぐらい is for amounts.