Cool MateBad vs Not good
When to use each in English, with meaning, register, and examples.
Bad
Top 1,000 (very common)A1adjective
Not good
Top 2,000 (common)
Most common: Bad
| Bad | Not good | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/bæd/","/wɜːs/","/wɜːst/"]/🇺🇸 /["/bæd/","/wɜːrs/","/wɜːrst/"]/ | 🇬🇧 //nɒt ɡʊd//🇺🇸 //nɑt ɡʊd// |
| Meaning | not good or harmful | Something that is bad or unsatisfactory. |
| Example | That was a bad performance by the team. | The food at the restaurant was not good at all. |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 2,000 (common) |
| CEFR level | A1 | - |
| Part of speech | adjective | |
| Collocations | be, look, sound, extremely, fairly, very, at, for, not half bad, be, look, sound, extremely, fairly, very, at, for, not half bad, be, look, sound, extremely, fairly, very, at, for, not half bad, be, look, smell, feel, extremely, fairly, very, about, be, look, sound, extremely, fairly, very, at, for, not half bad | not good enough, not good at, not good for |
| Antonyms | good, excellent, positive | - |
| Common mistakes | Using 'bad' instead of 'badly' as an adverb: e.g., 'He performed bad' instead of 'He performed badly'., Confusing 'bad' with 'ill' when referring to health. 'Ill' is usually used in formal contexts., Saying 'more bad' instead of 'worse' for comparative form. | 'Not good' is sometimes confused with 'bad', but they can have different tones., Learners may use 'not good' in every context; it's more informal., Some might incorrectly use 'not good' as a standalone response without context. |
| Usage notes | Use 'bad' to describe something that is of poor quality or morally wrong. It's generally appropriate in everyday conversation but can be too informal in professional settings. In formal writing, consider alternatives such as 'unfavorable' or 'detrimental'. | Use 'not good' in informal conversations to express dissatisfaction. In formal settings, consider using 'unsatisfactory' or 'below expectations'. |
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Frequently asked questions: Bad vs Not good
What's the difference between Bad and Not good?
Bad: not good or harmful Not good: Something that is bad or unsatisfactory.
Which is more common: Bad and Not good?
Bad is the most common in everyday English.
Can you show an example of each?
Bad: That was a bad performance by the team. Not good: The food at the restaurant was not good at all.
Can I use Bad and Not good interchangeably?
Not always. Bad and Not good are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.