Be on your/its last legs

Pro Tip 1/3

Metaphoric Use

This phrase often metaphorically describes extreme tiredness or effort.

After the all-nighter, she was on her last legs.

Pro Tip 2/3

Not Literal

Don't take it literally; it doesn't always involve legs.

The company was on its last legs, despite strong efforts to save it.

Pro Tip 3/3

Informal Context

It's casual, more likely heard in conversation than formal writing.

I can't go out tonight, I'm on my last legs from work.