off the charts

If something is “off the charts” it means that it is too big to even measure, or “unusually large in some way”. If a person weighs 250 kg, you could say that their weight is “off the charts“.  It’s “too big to measure” or “too big for a normal scale to measure”. It doesn’t have to be ONLY about physical size either.  Anything that is FAR bigger or FAR smaller than normal is “off the charts“. It can mean “great”, “terrible” or something else extreme.  The meaning is always obvious and it depends on the context of where it’s used. Examples will certainly help give you a clear idea of how this is used in real spoken English. 1.  Her singing is amazing.  It’s off the charts.  (She is an unbelievably great singer) 2.  I can’t believe how stupid he is.  It’s just off the charts!  (He is very very stupid) 3.  His strength is off the charts.  He’s the strongest person I’ve ever seen.