There is no single right answer to this question, in my opinion. Because for a clear answer, we need to know the definition of ‘money’. The answer may be different depending on what we consider ‘money’.
If we consider ‘money’ only as cash (banknotes and coins), we can say that the total amount of money in the world is around $7 trillion.
If we think about ‘money’ more widely and add gold ($7.8 trillion), bank accounts, and checking deposits, then the number would jump up to around $30 trillion.
In addition to the above, if we consider all stock markets, then we can say that the total amount of money on Earth is about $80 trillion.
These amounts of money continuously change because the amount of money in the world grows each year. For example, $100 hundred years ago has a different value than today’s $100. Inflation or deflation also influences the value of money.