Rule of 72 Calculator

The Rule of 72 is used to estimate how long it will take an investment to double. The Rule of 72 Calculator completes this calculation for you, it also allows you to compare investments using the rule of 72. There is an option to add the results to a table for comparison which you can print or email to yourself. (The table appears the first time you click the "Add to Table" button)

Rule Of 72 Calculator

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Rule of 72 Calculator. This image provides details of how to calculate the rule of 72 using a calculator and notepad. By using the rule of 72 formula, the Rule of 72 Calculator provides a true calculation of the interest rate on an investment and/or personal and home loans.

Using the Rule of 72 to Calculate How Your Investment Will Grow Over Time

Have you ever wondered how long will it take to double your money if you have invested in some fixed interest rate scheme offered by your bank? If yes, rule of 72 is the answer to your question. It is a term used in accounting to estimate the approximate time your investments will take to double in value.

Various banks offer FDs or term deposits on different rates of interest. It could be overwhelming for you to go through all such plans to choose the best, this is when the rule of 72 calculator can come to your help. It shows how your deposit will increase with each interest added to it over time and the good news is you get this result in the blink of an eye.

iCalculator's Rule of 72 calculator is here to help you know effortlessly how your investment will grow over the chosen term. If you want to invest right now or are considering investing soon, check the Rule of 72 online. Just enter the numbers: Interest Rate, Time Period, Amount, and get an easy-to-understand breakdown of balance instantly. You will know how your deposit is going to be doubled up. You can also print or email a copy to keep with you to share with your friends or trusted advisors to discuss your future plans.

Why use the rule of 72 calculator?

When investing your hard earned money it is essential to check each and every detail carefully. What majorly attracts everyone towards investment is the rate of interest, however, you might face a tough time while doing the actual calculation unless you are an accounting professional.

The Rule of 72 calculator can save you time and will be helpful in getting the best deal available in the market. It is very easy to use but gives you a detailed table for your investment. More benefits are as follows:

  • Time saving - It will save time as you don't actually have to go into the calculations.
  • Easy to use - You just have to contact or browse through different bank's websites to check the details and input into the calculator to get your personalized table.
  • Get the best option - You will end up getting the best options offered around when you use the calculator.

Things to be considered while using the calculator

There are few more aspects that you must be aware of before using the Rule of 72 online. Let's take a look at them now:

Compound Interest

The algorithm used in the calculator uses the rule of compound interest rate, which means it assumes that once you have made the investment you would not withdraw any cash, be it principal amount or interest. This way interest earned by you gets invested while reinvesting the principal amount.

Interest rate and fixed deposit term

Doubling your investment depends majorly on the interest rate offered by the bank but it also depends on what term you are going to select for the investment, this is possible that banks may offer less rate of interest for a very long term investment, so you should choose the appropriate term and then choose to reinvest the principal amount and accumulated earned interest.

Rule of 72 Formula

The actual equation is R x T = 72, where R is the interest rate and T is Time, or periods of time, in months or years, from this equation the required interest rate and number of payment periods can be extracted.

The Rule of 72 calculator also shows how the figures actually calculate over the time period if an amount is entered.

R x T = 72
T = 72 / R
R = 72 / T


  • R = Interest rate as a percentage
  • T = Time Periods

Factors that can affect your fixed deposits & financial resolutions

Below are some of the factors which you should consider before investing in any fixed deposit plan

  • Money lock - Your money will be locked for the entire period of investment and you will not be able to use it unless you are ready to give up the interest for the rest of the term. To overcome this risk, you can split your money, make small deposits and invest them into different banks if possible.
  • Banks and non-banking financial companies (NBFC) - There are many banks and NBFCs out there that are offering lucrative interest rates of fixed deposits, whatever you choose, always check the company's profile before investing.
  • Public or private sector banks - Both offer competitive rate of interests, do your research and compare before investing.

Investment in fixed deposits, the easy money?

There are many factors involved when it comes to investing in fixed deposits, certain risks are also involved but nothing that you cannot avoid with some research before investing. So, in short, investing in fixed deposits is not an easy task but with the Rule of 72 calculator you go through all the confusing details effortlessly and assess the returns on your investments with ease and accuracy.

Happy investing!!!