A currency counting machine or money counter is a device which calculates the amount of money that is being fed into it and can count either bundles of notes or an assortment of coins. Money counting machines have been traditionally made to be simply mechanical but the newer models use electronic components. The currency counter normally can give a readout of the total sum of money or if preprogrammed, can give you a total sum of the bills can split it into specific batches so it can easily be organized and stored.

Vending machines are a common example of where to find a bill counter. It is the reason why the vending machine always knows the amount you paid because the cash counter has the ability to identify the values of different bills and classify them accordingly. Also, in some new ATMs, there is a cash counter mechanism that allows for cash deposits without the use of envelopes. These new models have the ability to identify which bills have been inserted and not just calculates the total sum.

The first automatic currency counting machines were first introduced in the 1920s by the Federal Bill Counter Company of Washington, D.C., USA. These machines were designed to enhance the efficiency of employees in the Federal Reserve Bank and to decrease mistakes. The counter would stop once a programmed "batch" of bills was counted allowing the cashier or teller to place a wooden block to separate different batches from each other.

In 1962, newer technology developed for banknote counting machines were introduced by Tokyo Calculating Machine Works of Shinagawa, Tokyo, Japan. With its exponential increase in speed and accuracy, it quickly replaced older models and began to dominate the market.

In 1981, newer and computerized friction banknote counters were established with the advent of the REI High-Speed machine. This machine could count notes at speeds of 72,000 notes per hour and made obsolete the practice of manual sorting and eliminated labor-intensive manual counting completely. This innovative machine could also sort notes according to their value and discard counterfeit or heavily damaged notes. Many of these features can be found in many of today’s note counting machines, some of which can identify a note's security features (e.g. magnetic ink, ultraviolet ink, magnetic strip, note density etc.) to spot fake and damaged notes.

Furthermore, other extra features that can assist in everyday contact with cash were also added. For example, addition functions, batch functions and format recognition were also integrated to enhance the efficiency of bank tellers and employees worldwide.