How long is a piece of string?

Pro Tip 1/3

Uncertainty Context

Use when an exact number or amount cannot easily be given or is unknown.

How long will the meeting last? Well, how long is a piece of string?

Pro Tip 2/3

Non-literal Use

Understand it's a rhetorical question, not expecting a literal answer about string.

How successful will the project be? That's like asking how long is a piece of string.

Pro Tip 3/3

Avoid Overuse

Use sparingly to avoid vagueness in situations where specifics are important.

When budgeting, instead of asking 'How long is a piece of string?', seek exact figures.