也许 vs 大概 (yěxǔ vs dàgài): “perhaps” vs “probably”
The main difference between 也许 and 大概 is the degree of certainty. 也许 (yěxǔ) expresses a tentative guess, like “maybe” or “perhaps,” with roughly 50% probability. 大概 (dàgài) indicates a stronger likelihood, like “probably,” and also serves to mean “approximately” when followed by a number. Choosing the wrong one can confuse whether you are making a balanced guess or a confident estimate.
Both 也许 and 大概 express uncertainty, but they differ in the speaker's confidence level. 也许 suggests a pure guess with equal possibility of being true or false (approximately 50% certainty). It is used when the speaker has no strong evidence. 大概, in addition to meaning “probably” (higher confidence, around 70-80%), also functions as an adverb meaning “approximately” when used with numbers or quantities. This dual role makes 大概 more concrete in some contexts. While they can overlap in some guesses, choosing the correct term conveys the intended degree of certainty.
When to use each
Use 也许 when you are making a pure guess with roughly equal probability, often without strong evidence. It corresponds to “maybe” or “perhaps” in English. It is common in both spoken and written Chinese when speculating about uncertain outcomes.
Unlike 大概, 也许 cannot be used to mean 'approximately' nor to indicate a statistical likelihood higher than 50%.
Use 大概 when you are reasonably confident about a guess, indicating a higher probability (around 70-80%). Also use 大概 before numbers or quantities to mean 'approximately' or 'roughly', similar to 差不多. It is common in both speech and writing for estimates.
When 大概 precedes a number, it expresses approximation, not probability. For example, 大概十个人 means 'about ten people', not 'probably ten people'.
At a glance
| 也许 | 大概 | |
|---|---|---|
| Degree of certainty | ~50%, pure guess | ~70-80%, confident guess |
| Approximate number usage | Not used | Can mean 'approximately', e.g., 大概十个人 |
| Typical English equivalent | perhaps, maybe | probably, approximately |
| Formality | Neutral, common in all registers | Neutral, common in all registers |
Examples
- 也许也许他会同意。Yěxǔ tā huì tóngyì.Perhaps he will agree.Pure guess, no strong evidence.
- 大概她大概已经回家了。Tā dàgài yǐjīng huí jiā le.She has probably already gone home.Confident guess based on context.
- 大概这个包大概三公斤。Zhège bāo dàgài sān gōngjīn.This bag is about three kilograms.Approximate measurement, not probability.
Common mistakes
- Using 也许 when a higher probability is implied, e.g., 'He is probably sick' → use 大概.
- Using 大概 to mean 'maybe' (50/50) when a tentative guess is intended → use 也许.
- Confusing 大概 meaning 'approximately' with probability when used with numbers: 大概十个人 means 'about ten people', not 'probably ten people'.
- For approximate numbers, using 也许 instead of 大概 — 也许十个人 is unnatural for 'approximately ten people'.
FAQ
- When do I use 也许 vs 大概?
- Use 也许 for uncertain guesses (50% chance) and 大概 for more confident estimates (70-80%) or approximations with numbers.
- Can 大概 and 也许 be used interchangeably?
- In some contexts of low certainty, they may overlap, but 大概 implies higher confidence and also has a separate meaning of 'approximately' when used before numbers.
- Does 大概 always mean 'probably'?
- No. Before a number or quantity, 大概 means 'approximately' (e.g., 大概三天 'about three days'). In other contexts, it means 'probably' or 'most likely'.
- Is 也许 formal or informal?
- It is neutral and common in both spoken and written Chinese.