By ProDev Teach | Last Updated: May 2025
📘 Meaning & Usage
The expression ~に欠かせない is used to say that something is absolutely essential or indispensable to a certain activity, situation, or condition.
English Equivalents:
- Indispensable to
- Essential for
- Cannot do without
Structure:
Noun + に欠かせない
💡 Example Sentences
- ビタミンCは健康に欠かせない栄養素だ。
Vitamin C is an essential nutrient for good health. - この技術は現代社会に欠かせないものになっている。
This technology has become indispensable to modern society. - チームワークは成功に欠かせない要素だ。
Teamwork is an essential element of success. - 信頼関係は良好な人間関係に欠かせない。
Mutual trust is vital for good relationships.
📝 Grammar Notes
The word 欠かせない is the negative potential form of 欠く (to lack), so it literally means “cannot be lacking.” It is used to describe something that must be present.
Used with:
- Concepts: 努力 (effort), 信頼 (trust), 健康 (health), etc.
- Objects: テクノロジー (technology), 情報 (information), etc.
✏️ Practice Exercises
1. Fill in the blanks
- 運動は健康( )。
- 水は生きる上で( )。
- 成功には努力( )。
✔ Answers:
- 運動は健康に欠かせない。
- 水は生きる上でに欠かせない。
- 成功には努力に欠かせない。
2. Translate into Japanese
- Trust is indispensable to friendship.
- Teamwork is essential for success.
✔ Suggested Answers:
- 信頼は友情に欠かせない。
- チームワークは成功に欠かせない。
📚 Related Grammar
- ~抜きでは(ぬきでは): Without… (cannot do something)
- ~なしでは: Without… (similar nuance)
- ~なくてはならない: Must have / must do
🧠 Summary
- ~に欠かせない = “Indispensable / Cannot be done without”
- Level: JLPT N1
- Form: Noun + に欠かせない
- Usage: Used to emphasize importance or necessity of something

I’m a software engineer based in Japan, with experience in developing web and mobile applications. I’m passionate about technology, especially in DevOps, AI, and app development using platforms like AWS, Flutter, and Node.js. My goal is to build a website that shares knowledge about the Japanese language and IT, helping everyone learn and grow more easily in the digital era.