Cool MateWhat for vs Why
When to use each in English, with meaning, register, and examples.
What for
InformalTop 5,000 (fairly common)
Why
High-frequency chunkA1adverb
Most formal: WhyMost common: Why
| What for | Why | |
|---|---|---|
| Pronunciation | 🇬🇧 //wɒt fɔː//🇺🇸 //wɑt fɔr// | 🇬🇧 /["/waɪ/"]/🇺🇸 /["/waɪ/"]/ |
| Meaning | A phrase asking about the purpose of something. | A word used to ask for a reason or explanation. |
| Example | I forgot my umbrella; what for is it raining anyway? | I asked her why she was late. |
| Register | Informal | Neutral |
| How common | Top 5,000 (fairly common) | High-frequency chunk |
| CEFR level | - | A1 |
| Part of speech | adverb | |
| Collocations | ask what for, wonder what for, what for this, say what for, know what for | ask why, wonder why, no reason why |
| Antonyms | - | because, therefore, so |
| Common mistakes | Confused with 'what is for' which is less common., Used in formal contexts, which can sound awkward., Omitted the subject, making the question unclear. | Omitting 'why' in a question that needs it., Using 'why' in a statement instead of a question., Confusing it with 'when' or 'how'. |
| Usage notes | Used in casual conversation to inquire about reasons or purposes. It's not usually used in formal writing. | Used to inquire about reasons. Generally suitable for most contexts, but avoid in very formal writing. Often starts a question. |
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Frequently asked questions: What for vs Why
What's the difference between What for and Why?
What for: A phrase asking about the purpose of something. Why: A word used to ask for a reason or explanation.
Which is more formal: What for and Why?
Why is the most formal of these.
Which is more common: What for and Why?
Why is the most common in everyday English.
Can you show an example of each?
What for: I forgot my umbrella; what for is it raining anyway? Why: I asked her why she was late.
Can I use What for and Why interchangeably?
Not always. What for and Why 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.