Cool MateBy whom vs Who
When to use each in English, with meaning, register, and examples.
By whom
FormalBeyond 10,000 (less common)
Who
High-frequency chunkA1pronoun
Most formal: By whomMost common: Who
| By whom | Who | |
|---|---|---|
| Pronunciation | 🇬🇧 //baɪ huːm//🇺🇸 //baɪ hum// | 🇬🇧 /["/huː/"]/🇺🇸 /["/huː/"]/ |
| Meaning | Who did something | A word used to ask about a person. |
| Example | The painting was created by whom? | Who is that woman? |
| Register | Formal | Neutral |
| How common | Beyond 10,000 (less common) | High-frequency chunk |
| CEFR level | - | A1 |
| Part of speech | pronoun | |
| Collocations | by whom it was created, by whom is the decision made, by whom should I ask | who is, who are, who knows |
| Antonyms | - | someone, somebody, anyone, anybody |
| Common mistakes | Incorrectly using 'who' instead of 'whom' in formal contexts., Forgetting to use 'by' when forming the question. | Using 'who' for objects instead of 'whom'., 'Who' used incorrectly after prepositions like 'to'. |
| Usage notes | Use in formal contexts, such as writing or speeches. It's less common in casual conversation. | Used to inquire about someone's identity; appropriate in both formal and informal settings. Avoid using it in contexts where specifics are required, like in legal or detailed reports. |
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Frequently asked questions: By whom vs Who
What's the difference between By whom and Who?
By whom: Who did something Who: A word used to ask about a person.
Which is more formal: By whom and Who?
By whom is the most formal of these.
Which is more common: By whom and Who?
Who is the most common in everyday English.
Can you show an example of each?
By whom: The painting was created by whom? Who: Who is that woman?
Can I use By whom and Who interchangeably?
Not always. By whom and Who 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.