〜おきに: 'Every Other' / 'At Intervals Of' (Meaning + Examples)
What it means
〜おきに describes something that repeats at regular intervals, with a gap of X between each occurrence. You attach it to a quantity — a number plus a counter (日, 週間, メートル, etc.):
ヤッタンは1日おきにジョギングをします。
ヤッタンは いちにちおきに ジョギングを します。
Yattan goes jogging every other day.
Run, skip a day, run — a one-day gap between runs.
この道は2メートルおきに木が植えてあります。
この みちは にメートルおきに きが うえて あります。
On this road there's a tree planted every 2 meters.
A 2-meter gap between each tree.
モチは1週間おきに美容院へ行きます。
モチは いっしゅうかんおきに びよういんへ いきます。
Mochi goes to the salon every other week.
The mental image is a fence: the posts are the events, and おきに tells you the size of the gap between posts.
How to form it
| You want to say | Pattern | Example |
|---|---|---|
| every other day | number + counter + おきに | 1日おきに |
| every 2 meters | number + counter + おきに | 2メートルおきに |
| every other week | number + counter + おきに | 1週間おきに |
| at 3-hour intervals | number + counter + おきに | 3時間おきに |
There's no conjugation — おきに is fixed. Just place it directly after the quantity, then continue with your verb or clause.
The "gap" logic (why 1日おきに = every other day)
This is the heart of おきに. Because it counts the gap between events, you have to add the gap to one unit to get the real cycle:
- 1日おきに → gap of 1 day → do it, skip 1 day, do it → effectively every 2nd day = "every other day."
- 2日おきに → gap of 2 days → do it, skip 2 days → effectively every 3rd day.
So with time, the cycle length is roughly interval + 1 unit. With distance, people usually read it more directly — 2メートルおきに just means trees spaced 2 meters apart. Native usage with larger time units (週間, ヶ月) can get loose in casual speech, so if precision matters, many people prefer the clearer 〜ごとに below.
先生は2日おきにテストをします。
せんせいは ふつかおきに テストを します。
The teacher gives a test every third day.
Gap of 2 days between tests, so the cycle is 3 days.
〜おきに vs 〜ごとに
These overlap in English ("every X"), but they count differently:
- 〜おきに = the gap between occurrences. 3日おきに = a 3-day gap → roughly every 4th day.
- 〜ごとに = every X, counted inclusively. 3日ごとに = every 3 days (no skipping).
So 3日ごとに and 2日おきに describe the same real-world cycle (a 3-day rhythm). When you mean a plain, inclusive "every X," 〜ごとに is the safer choice.
弟は3日ごとに部屋を掃除します。
おとうとは みっかごとに へやを そうじします。
Yattan's brother cleans his room every 3 days.
ごとに counts inclusively: a clean cycle of exactly 3 days.
Common mistakes
- Reading 1日おきに as "every day." It means every other day — there's a one-day gap. "Every day" is just 毎日.
- Treating おきに and ごとに as identical. 3日おきに (gap of 3 → ~every 4th day) ≠ 3日ごとに (every 3 days). Match the counting style to your meaning.
- Forgetting the counter. You can't say 1おきに — you need number + counter: 1日おきに, 2時間おきに.
- Adding を or が before it. おきに attaches straight to the quantity: 5分おきに (✓), not 5分をおきに.
Quick recap
- 〜おきに = at intervals, with a gap of X between each occurrence.
- For time, the real cycle is about interval + 1 unit: 1日おきに = every other day.
- For distance, it reads more directly: 2メートルおきに = spaced 2 meters apart.
- 〜ごとに = "every X," counted inclusively — use it when you want a plain, unambiguous interval.
Your turn
Choose the correct interval meaning for 〜おきに.
Start the 5-question drill →Frequently asked questions
Does 1日おきに mean 'every day' or 'every other day'?
Every other day. おきに marks the gap between events, so 1日おきに leaves a one-day gap: do it, skip a day, do it. 'Every day' is 毎日.
What's the difference between おきに and ごとに?
おきに counts the gap between occurrences, while ごとに counts inclusively. 3日ごとに = every 3 days; 2日おきに describes the same cycle (a 2-day gap, so every 3rd day).
How do I attach おきに?
Put it directly after a number plus a counter: 5分おきに, 2メートルおきに, 1週間おきに. No particle goes in between.
Is おきに ambiguous?
With time units it can be read loosely in casual speech, especially with weeks or months. If you need a clear, inclusive 'every X,' use 〜ごとに instead.