〜おきに
oki ni
By Nihongo PathUpdated
Meaning
every other… / at intervals of… (skipping the stated span between events)
〜おきに means the stated span is left empty between events: 一日おきに "every other day", 六時間おきに "every six hours (six-hour gaps)", 一メートルおきに "at one-metre intervals". Think of the span as the gap you skip. With minutes and hours it usually feels the same as ごとに; with days the difference matters.
Timetables, medicine instructions, spacing of objects. Always with a number + counter.
Formation
V = verb, N = noun, A = adjective.
Number + counter + おきに (一日おきに, 十五分おきに, 一メートルおきに)Number + counter + おきの + Noun (一週間おきの練習)
Visual diagram
月曜日
Do it.
火曜日
Skip (the one-day gap).
水曜日
Do it.
木曜日
Skip.
金曜日
Do it. → 'every other day'
月曜日
Do it.
火曜日
Skip (the one-day gap).
水曜日
Do it.
木曜日
Skip.
金曜日
Do it. → 'every other day'
Natural examples
この薬は六時間おきに飲んでください。
このくすりはろくじかんおきにのんでください。
Take this medicine every six hours.
Six-hour gaps between doses.
バスは十五分おきに来る。
バスはじゅうごふんおきにくる。
The bus comes every fifteen minutes.
Fifteen-minute intervals.
一日おきにジョギングをしている。
いちにちおきにジョギングをしている。
I jog every other day.
Every other day (skip one).
道には一メートルおきに木が植えられている。
みちにはいちメートルおきにきがうえられている。
Trees are planted along the road at one-metre intervals.
Spatial intervals.
このクラスは一週間おきに行われる。
このクラスはいっしゅうかんおきにおこなわれる。
This class is held every other week.
One-week gap between classes.
Similar grammar and the difference
Counts every instance (一日ごとに = every day). Compare side by side
〜に一回 / 〜に一度
'Once per (period)': 二日に一回 ≈ 一日おきに.
〜間隔で
'At intervals of' in written or technical style (十分間隔で).
Common mistakes
- ✗
- 一日おきに = every day
- ✓
- 一日おきに = every other day
- Why
- The stated span is the gap, so one day is skipped.
- ✗
- 会うおきに
- ✓
- 会うたびに / 会うごとに
- Why
- おきに needs a number + counter; it cannot follow a verb.
- ✗
- 月曜日おきに
- ✓
- 一週間おきに / 隔週の月曜日に
- Why
- おきに takes a quantity, not a day name.
With small units (分, 時間) native speakers often use おきに and ごとに interchangeably. 二日おきに = every three days (two-day gap). In 聴解, timetable announcements use 〜分おきに.
JLPT N3 tips
On the exam
- A number + counter and the idea of skipping → おきに.
- If the blank follows a verb or a group noun, おきに is impossible; choose ごとに / たびに.
- For 'every other day/week', おきに is the only correct answer.
Frequently asked questions
What does 〜おきに mean?
every other… / at intervals of… (skipping the stated span between events). 〜おきに means the stated span is left empty between events: 一日おきに "every other day", 六時間おきに "every six hours (six-hour gaps)", 一メートルおきに "at one-metre intervals". Think of the span as the gap you skip. With minutes and hours it usually feels the same as ごとに; with days the difference matters.
How do you form 〜おきに?
Number + counter + おきに (一日おきに, 十五分おきに, 一メートルおきに) / Number + counter + おきの + Noun (一週間おきの練習). V = verb, N = noun, A = adjective.
When is 〜おきに used?
Timetables, medicine instructions, spacing of objects. Always with a number + counter.
What is the difference between 〜おきに and 〜ごとに?
Counts every instance (一日ごとに = every day).
What is the difference between 〜おきに and 〜に一回 / 〜に一度?
'Once per (period)': 二日に一回 ≈ 一日おきに.
What is a common mistake with 〜おきに?
Wrong: 一日おきに = every day Right: 一日おきに = every other day The stated span is the gap, so one day is skipped.
Quick check
このバスは二十分（ ）に来ます。