深い vs 濃い
JLPT N4 vocabulary · what is the difference?
深い is about depth — how far down or how far in something goes, literally for water and forests and figuratively for meaning, thought and relationships. 濃い is about concentration — how much of something is packed into a given amount, which is why coffee, flavour, colour and fog are 濃い. 濃いコーヒー is strong coffee; 深い意味 is a deep meaning.
When to use each
深い
ふかい
Use 深い when there is a distance downward or inward: water, holes, snow, forests. Figuratively it covers meaning, thought, sleep, and close relationships. Its opposite is 浅い.
この川は深いので気をつけてください。
このかわはふかいのできをつけてください。
This river is deep, so please be careful.
その言葉には深い意味があります。
そのことばにはふかいいみがあります。
Those words have a deep meaning.
濃い
こい
Use 濃い when something is concentrated or dense: strong tea or coffee, heavy seasoning, dark colours, thick fog, thick hair. Its opposite is 薄い.
濃いコーヒーが好きです。
こいコーヒーがすきです。
I like strong coffee.
今朝は霧が濃かったです。
けさはきりがこかったです。
The fog was thick this morning.
Sentences where only one works
このスープは味が濃いです。
このスープはあじがこいです。
This soup is strongly flavoured.
Flavour strength is concentration, so 濃い. 味が深い exists but means complex and rounded, not heavily seasoned.
深い海には光が届きません。
ふかいうみにはひかりがとどきません。
Light doesn't reach the deep sea.
Physical depth, measured downward: only 深い.
濃い青のシャツを買いました。
こいあおのシャツをかいました。
I bought a dark blue shirt.
Colour strength is 濃い, with 薄い for pale. 深い青 turns up in literary writing, but 濃い is the everyday word.
二人は深い関係です。
ふたりはふかいかんけいです。
The two of them are close.
Relationships have depth, not concentration, so 深い.
Common mistakes
深いコーヒー
濃いコーヒー
The strength of a drink is concentration. 深い here sounds like the cup itself is physically deep.
濃い意味
深い意味
Meaning is measured by depth. 濃い意味 is not a phrase Japanese speakers use.
Frequently asked questions
How do I say weak coffee?
薄いコーヒー. 薄い is the regular opposite of 濃い for drinks, flavour and colour. The opposite of 深い is 浅い.
Can 濃い describe a person?
Colloquially yes — 濃い人 means someone with a larger-than-life, intense presence. It is casual and can be teasing, so use it carefully.
Is 味が深い wrong, then?
No, it just means something else: a flavour with depth and complexity, the kind of praise you give a broth or a wine. 味が濃い is simply about strength of seasoning.