That is a common misconception that got started as a misunderstanding of Milton Friedman's (reasonable) money multiplier equation. Banks cannot lend more money than they have - if they could, then you could start a bank and multiply your own money. The money multiplication that banks can do is take the money that party B has received for selling something and loan it back to to party A, who can use it to buy something from party B again.

A zero percent reserve requirement does not lead in all cases to infinite inflation, because banks are also afraid of a default. Bank's desire to avoid defaults adds another fraction to their reserve ratio and limits money multiplication even when the Fed would technically allow it to proceed infinitely.

Another thing you should know is that Fed chairmen have said that Friedman's equation underestimates bank's ability to create money, because in practice the Fed will allow any bank that desires liquidity to borrow it. The Fed, especially post-great-depression, will happily loan banks however much they needed to cover their reserve requirements, meaning that even before the ratio was set at zero, the number of times a single dollar could be spent was decided primarily by a balance of interest rates and fear of defaults.

Is there a misconception in the text of my previous comment? You seem to be describing a misconception that as far as I can tell isn't one I hold or one I expressed in my previous comment.

The misconception in your comment is that the reserve requirement is what limits a bank's ability to create money by extending loans.

I'm no expert, and I know that banking is a lot more complicated in practice, and that reserve requirements in the U.S. (even before they went to zero) were apparently not a significant factor in what actually put a ceiling on banks' ability to lend. There were apparently all sorts of tricks banks used to not be bound in practice to reserve requirements.

Yes, reserve requirements are not a significant factor, because in addition to reserve requirements banks are also subject to capital requirements. Moreover banks need reserves to operate anyway regardless of whether they're mandated by law or not. Finally they're also constrained by the demand for loans, which isn't infinite.

it's the capital requirements or capital to risk weighted assets ratio that restrict lending, not reserve requirements. reserve requirements are to protect runs by depositors and capital requirements are to protect the bank against bad loans.

at the end of every month and especially every quarter the bank submits its capital ratio and a bunch of other calculations to the regulators. if the ratio isn't good it has to increase capital reserves. if the ratio is good it can do share buybacks and dividends.

https://en.wikipedia.org/wiki/Basel_III

> loan out much more than 1 dollar

They can't loan out more than the deposits they have.

Why not? A bank could have 0 depsitors, but could have received money from investors.

That's not the sort of bank being talked about here in terms of "money multiplication." That's more like a VC firm or other institution.

If you could open a bank, accept 10 dollars in deposits, and loan out 100, you'd do it! You'd loan it out to your best friend and keep the cycle going until you're rich AF.

You can't loan out more than you have, but even loaning out 10 of 10 dollars has some risk - if someone comes for their money and you can't get your money back from the people you loaned it to. And it definitely increases money in circulation since it's not parked there. But it's not a magic money printing machine.

The Federal Reserve says you may loan out 100% of your deposits. They didn't say you could loan out however much you have in investors' money, or 200% of your deposits.

Can you share some resources where I can learn about this? Thanks

The reserve requirement ratio does not do what you think it does. It is the amount of money that the bank is required to keep in its account at a Federal Reserve Bank as a ratio of deposits. Note that literal cash sitting in a vault does not count one iota towards satisfying this reserve ratio.

Bank regulations have moved one from having such a specific requirement. Nowadays, you essentially need a minimum amount of equity per risk-weighted assets. So you need something like $8 in cash for every $100 in loans you give out.