几 vs 多大 (jǐ vs duō dà): asking age and size
Both 几 and 多大 can be used to ask about age, but they differ in connotation and typical use. 几 is a general question word for 'how many' and requires a measure word such as 岁 (suì, 'year old') to ask age, usually for young children (up to about 10). 多大 is a fixed phrase meaning 'how old/big' and is used for age of any person (especially adults) and for size/measurements. Choosing the wrong term can sound childish or impolite.
In Mandarin, 几 (jǐ) means 'how many' and always needs a measure word when asking about quantity. For age, the phrase is 几岁 (jǐ suì), limited to children (typically under 10 – 12). 多大 (duō dà) is a general expression for 'how old' (any age, especially adults) and also for size (e.g., clothing, shoes). While both can ask about age, 几岁 implies a small number is expected, and 多大 is more neutral and polite for adults. For size/measurements, only 多大 (or 多大尺寸) is correct.
When to use each
Use 几 to ask 'how many' of something, always followed by a measure word. For age, the specific phrase is 几岁, but only for young children whose age is a low number (e.g., 1–10). It is also used for other predictable small quantities (e.g., 几本书 'how many books').
几 implies the answer is expected to be a small number (roughly under 10). Using 几岁 with adults sounds unnatural or childish.
Use 多大 to ask about age for any person, especially adults, and to ask about size/measurements of objects (e.g., shoes, clothes, rooms). It is the standard, polite way to ask an adult's age. For very old people, 多大年纪 (duō dà niánjì) or 高寿 (gāo shòu) are more respectful.
多大 literally means 'how big' and can be used for both age and physical dimensions. In some contexts, it may be vague, so context clarifies whether age or size is meant.
At a glance
| 几 | 多大 | |
|---|---|---|
| Word type | Question word + measure word required | Fixed phrase (adjective + adverb) |
| Age question phrasing | 几岁 – for children | 多大 – for any age, especially adults |
| Expected answer range | Expects small numbers (0–10) | No numerical expectation |
| Used for size/measurements | No (几尺寸 is incorrect; use 多大尺寸) | Yes (多大 alone asks 'how big?') |
| Politeness for adults | Not polite – sounds childish | Standard and polite |
Examples
- 几你孩子几岁？Nǐ háizi jǐ suì?How old is your child?几岁 is only for young children.
- 多大你多大？Nǐ duō dà?How old are you?Standard way to ask any adult's age.
- 多大这双鞋多大？Zhè shuāng xié duō dà?What size are these shoes?多大 used for size, not 几.
- 几你几岁？Nǐ jǐ suì?How old are you?✗ Sounds childish if said to an adult. Use 多大 instead.
- 多大她多大年纪了？Tā duō dà niánjì le?How old is she? (about an elderly person)多大年纪 is a respectful variant for older people.
- 几你有几本书？Nǐ yǒu jǐ běn shū?How many books do you have?几 with a measure word (本) for quantity, not age.
Common mistakes
- Using 几岁 for an adult (e.g., *你几岁？* to a colleague) – sounds childish; use 多大.
- Using 多大 to ask a child's age (e.g., *你多大？* to a 3-year-old) – possible but 几岁 is more natural for young kids.
- Using 几 alone without a measure word to ask about age (e.g., *你几？* is incorrect; must say *几岁*).
- Using 几尺寸 for size (e.g., *这双鞋几尺寸？*) – correct is *这双鞋多大？*.
FAQ
- When do I use 几 vs 多大 for age?
- Use 几岁 for children (roughly under 10–12 years old) and 多大 for teenagers and adults. 几 implies a small number, so it's inappropriate for adults. For elderly people, consider using 多大年纪 or 高寿 for extra respect.
- Can I use 多大 to ask about size of a shirt?
- Yes. 多大 is the standard way to ask 'how big' or 'what size' for clothing, shoes, rooms, etc. For example: 你这件衬衫多大？ (What size is this shirt?). Do not use 几 for size questions.
- Is 几岁 ever used for adults in a joking way?
- Occasionally, adults may ask each other 你几岁？ in a playful or sarcastic tone (e.g., when someone acts childishly). But in normal, polite conversation, avoid it.
- What about asking a baby's age?
- For babies (under 1 year old), you can still use 几岁, but sometimes people ask 几个月？ (jǐ gè yuè) 'how many months?' because babies' ages are often given in months. For toddlers, 几岁 is fine.