Money Supply Calculator - M1, M2, and M3

The money supply calculator turns commonly cited monetary aggregates into a single worksheet. Students, analysts, and journalists use it to reconstruct M1, M2, and M3 from currency, deposits, and money-market funds, then to see how a required reserve ratio maps into a simple money multiplier. Official statistical agencies publish seasonally adjusted series with many more instruments than this teaching layout, so treat the result as a transparent identity check rather than a substitute for a central-bank release. M1 is currency in circulation plus demand deposits, the balances most readily spent. M2 adds time deposits and retail money-market funds, capturing near-money savings that can move into spending with a short delay. M3 adds large time deposits and institutional money-market funds, which sit further from household transaction accounts. The simple money multiplier is 1 divided by the reserve ratio, shown as 100 / reserve-ratio percent. A 10% reserve ratio implies a 10× multiplier; a 5% ratio implies 20×. That textbook multiplier describes the maximum expansion of deposits if banks lend every excess reserve and the public does not drain cash. Real banking systems hold excess reserves, face capital rules, and respond to interest on reserves, so the observed multiplier is usually smaller. Use the money supply calculator when comparing textbook examples, when checking whether a homework identity is internally consistent, or when illustrating how a reserve-ratio change would scale potential deposit creation. Keep units consistent—billions or millions are fine as long as every input uses the same scale. The headline result is M3 so the broadest aggregate is easy to quote, while M1, M2, and the multiplier remain visible for narrower questions. Definitions drift across countries and over time. Some M2 series include savings deposits and retail money funds but exclude large CDs; some countries stopped publishing M3. Sweep accounts, repurchase agreements, and central-bank reserves are outside this form. The calculator does not estimate the monetary base, velocity, inflation, or interest rates. Recalculate when a source restates an aggregate, and cite the original statistical release whenever the number will appear in a report or classroom assignment.