箱の内に手紙が入っている。
There is a letter inside the box.
I'll finish it within an hour.
Used in the pattern 〜のうち to indicate selection or comparison within a group. Usually written in kana.
Which do you like best among these three?
He is the tallest among my friends.
in (a state); amidst; with
Pattern 〜のうちに after a noun representing a state or condition: in secret, in chaos, with success, etc. Also written 裡 or 裏 in literary contexts. Usually written in kana.
We completed the project with success.
The meeting began amidst confusion.
within oneself; one's inner thoughts
Refers to one's inner feelings, thoughts, or heart. Often used in expressions like 心の内 or 胸の内.
He rarely shows his inner thoughts.
I opened up about my feelings.
we; our company; our organization
Only when written 内
Humble first-person plural used in business or formal contexts to refer to one's own group. Antonym: そと (outside group). Usually written in kana.
That is what we have decided within our company.
I will check with someone from our organization.
Only when written 内
Refers to one's own home or family. Also written 家. Usually written in kana in modern usage.
See also: うち
I'll relax at home today.
Everyone in my family likes dogs.
my spouse; my husband; my wife
Only when written 内
Humble reference to one's own spouse. Gender-neutral but context-dependent.
My husband is out right now.
My wife has been in your care.
signed on behalf of husband by wife
Only when written 内
Archaic epistolary convention: wife signs a letter after the husband's name using 内. Very rare in modern Japanese.
At the end of the old letter, it says 'Tarō uchi', meaning signed by his wife on his behalf.
Only when written 内
Kansai dialect first-person pronoun, primarily used by women and children. Casual and regional.
I don't know anything about that. (Kansai dialect)
imperial palace grounds; emperor
Only when written 内
Archaic. Refers to the imperial palace or, by extension, the emperor. Not used in modern Japanese outside historical contexts.
Commoners were not allowed inside the imperial palace grounds.
I finished my homework within an hour.
Let's go home before it starts raining.
Three out of the ten people agreed.
My hand was moving unconsciously.
He kept his sadness hidden inside.
This company clearly distinguishes between insiders and outsiders.
家 refers to the physical house or building, while 内 refers to one's home as a personal, familial space.
内 refers broadly to the inside or interior of something, while 奥 emphasizes the deep, far, or hidden part reached only after going further in.
family circle; in-group; one's own circle · private matters; internal affairs · conservative; moderate; on the low side · pigeon toe; in-toeing
shy; bashful; timid; reserved
makuuchi; top sumo division
inner thigh; inside of the thigh · pigeon-toed; toes turned inward · uchi-mata (judo throw)
too; extremely; so; super
palm of one's hand · skill; control; hidden intentions · one's hand (in card games or mahjong)
private; confidential; internal; within a closed group
inner loop; inner track; inner lane
gift for close relatives or friends; return gift for a family celebration · family celebration; private celebration
internal factional violence; infighting within a student group
makunouchi bento; box lunch with rice and assorted side dishes · makuuchi; top division of professional sumo · intermission; interlude between acts
internal conflict; family quarrel; domestic trouble
inner moat; moat within the castle walls
interior lining; inner paneling
lion at home, mouse abroad
indoor hot-spring bath
deposit; money paid on account; bargain money
inner thigh; inside of the thigh
indoor bath; private bath
inside story; lowdown; inner workings · inner curtain (historical military)
bales forming the edge of the sumo ring
godown within a compound; warehouse within a building complex
inside of a helmet; hidden circumstances
inner courtyard; quadrangle
inside pocket; bosom · real intentions; inner thoughts; true state of affairs
internal door; inner door
included number; number within a total
Search-only form; used in the sense of 'amidst' or 'in a state of'.
Rare alternate kanji; 内 is overwhelmingly preferred.