安い vs 低い
JLPT N5 vocabulary · what is the difference?
安い means cheap — it is only about cost. 低い means low in physical height or on a scale, like a mountain, a voice or a temperature. The price itself is 値段が安い, not 値段が低い, so a cheap shop is 安い店 and a short person is 背が低い.
When to use each
安い
やすい
Use 安い only about money: the price of goods, tickets, rent, a shop's prices. It can describe the thing being sold or the price itself.
この店は野菜が安いです。
このみせはやさいがやすいです。
The vegetables are cheap at this shop.
もっと安いホテルを探しています。
もっとやすいほてるをさがしています。
I'm looking for a cheaper hotel.
低い
ひくい
Use 低い for physical height — a mountain, a building, a person's stature — and for anything on a scale: temperature, a voice, a level, a percentage.
今日は気温が低いです。
きょうはきおんがひくいです。
The temperature is low today.
弟は私より背が低いです。
おとうとはわたしよりせがひくいです。
My little brother is shorter than me.
Sentences where only one works
この店は値段が安いです。
このみせはねだんがやすいです。
The prices at this shop are low.
English says 'low prices', but Japanese pairs 値段 with 安い. 値段が低い is the classic learner error.
この山は低いので、子どもでも登れます。
このやまはひくいので、こどもでものぼれます。
This mountain is low, so even children can climb it.
Physical height, so only 低い works.
彼は声が低い。
かれはこえがひくい。
He has a deep voice.
Pitch is a scale, so 低い; 安い has no such sense.
安いレストランですが、味はいいです。
やすいれすとらんですが、あじはいいです。
It's a cheap restaurant, but the food is good.
Cost only, so 安い; 低いレストラン would describe a short building.
Common mistakes
値段が低いです。
値段が安いです。
'Low price' translates word for word into 値段が低い, but the standard collocation is 値段が安い. Formal writing does use compounds like 低価格, which is why the mistake feels plausible, but 値段が低い is not natural in ordinary sentences.
この山は安いです。
この山は低いです。
安い can never mean physically low. This sentence says the mountain is inexpensive.
気温が安いです。
気温が低いです。
Anything on a measured scale — temperature, level, rate — takes 低い. 安い is restricted to money.
Frequently asked questions
So is 値段が低い always wrong?
In everyday sentences, yes — use 値段が安い. You will meet 低い with price-related nouns in formal economic writing, such as 価格水準が低い, but that is a different register and not a model for conversation.
Does 安い have a negative meaning too?
It can. 安っぽい means cheap-looking or tacky, and phrases like 安い男 suggest someone with no self-respect. Plain 安い about goods is neutral or positive.
How do I say someone is short?
背が低い. Do not use 短い, which is for objects like a rope or a skirt, and never 安い.