# Interactive MTA/New York MetroCard Calculator to Avoid Overpaying

Below, I outline the methods used in the above chart for avoiding leftover amounts when purchasing rides on a MetroCard, as well as thresholds for purchasing unlimited rides for both 7-day and 30-day passes.

#### MTA MetroCard Information and Cost Optimization

The Metrocard bonus adds 5% to the total purchase price, which can be represented as follows:

where

*T*is the total added to the MetroCard,

*P*is the amount paid, and the 1.05 is the total plus the added 5%.

Therefore, if we want to purchase 5 rides and avoid having leftover change on the MetroCard, we need to calculate the approximate amount (in multiples of $0.05 per MTA's requirement) to add to the card to get closest to the cost of 5 rides while also incorporating the extra 5%. This can be calculated in the following manner:

### NOTE:

Remember to always round -UP- when calculating the total for the desired number of rides, otherwise you will end up with a large amount left over just shy of another ride.#### Interactive MTA/New York MetroCard Calculator Description

Using the method above and an algorithm that optimizes cost and unlimited ride options, I created the interactive chart at the top of this page that shows subway riders when to buy single purchase amounts, 7-day unlimited passes, and 30-day unlimited passes. For cases beyond 7 days in the city, I have also included an optimized mix of single pay options and 7-day options. For amounts greater than the 30-day unlimited cost, I have recommended the 30-day unlimited pass. In every case, the chart shows the rider which option is financially advantageous based on the days in the city and rides per day.

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