〜おきに: 'Every Other' / 'At Intervals Of' (Meaning + Examples)
When you'd reach for it
〜おきに describes something that repeats at regular intervals, with a gap of X between each occurrence. You reach for it when you want to stress the space between events rather than the events themselves. You attach it to a quantity — a number plus a counter (日, 週間, メートル, etc.). The mental image is a fence: the posts are the events, and おきに tells you the size of the gap between posts.
Building the interval
There's no conjugation — おきに is fixed. Just place it directly after the quantity, then continue with your verb or clause:
| 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 |
In real situations
Here it is doing its everyday work — a repeated action with a fixed gap in between:
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.
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.
And with distance it spaces things out evenly rather than in time:
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.
Getting the gap right
The heart of おきに — and where it trips people up — is that it counts the gap between events, so you 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." Reading it as "every day" (毎日) is the classic mistake.
- 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.
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.
The other pitfall is treating おきに and 〜ごとに as identical. They 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 — and because native usage of おきに with larger time units (週間, ヶ月) can get loose in casual speech, many people prefer it when precision matters.
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.
Two smaller slips round out the list: don't drop the counter (you can't say 1おきに — you need 1日おきに, 2時間おきに), and don't add a particle before it (5分おきに ✓, not 5分をおきに).
The short version
- 〜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.
Practice it
Choose the correct interval meaning for 〜おきに.
＿＿＿に入れるのに最もよいものを選びなさい。
Choose the grammar pattern that best completes the sentence.
＿＿＿薬を飲みます。
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.
More N4 grammar to explore
Keep going with related patterns at the same level:
- 〜しか〜ない — 〜しか always pairs with a negative verb to mean 'only / nothing but,' with a 'not enough' nuance: 百円しかない. Learn the formation, particle rules, and しか vs だけ.
- 〜ているところ — ところ marks a moment in time: 〜るところ = about to do, 〜ているところ = right in the middle of doing, 〜たところ = just finished. Learn all three phases with clear examples.
- 〜てみる — 〜てみる means to do something and see how it goes — to try it out. Learn the て-form + みる formation, how みる conjugates (てみた, てみよう), and how it differs from 〜たい.
- 〜てすみません — 〜てすみません attaches すみません to a verb's て-form to say 'sorry for (doing).' Learn the formation, the negative 〜なくてすみません, and polite 〜て申し訳ありません.
- 〜てよかった — 〜てよかった adds よかった to a verb's て-form to say 'I'm glad that…': 日本に来てよかった. Learn the formation, the negative 〜なくてよかった, and how it shows relief.
- 全然・あまり・そんなに + Negative — 全然, あまり, and そんなに pair with a negative to say 'not at all,' 'not very,' and 'not so much.' Learn each pattern, the casual 全然 + positive, and the common negative-dropping mistake.