Retirement Calculator

What this tool does

The Retirement Calculator inflates today’s monthly expenses to your retirement date, then finds the corpus needed to fund rising withdrawals until your chosen age. It compares that target with the future value of your current savings and monthly investments and tells you how much more to invest each month.

Retirement planning comes down to two numbers: how much money you will need on the day you stop working, and how much you must invest until then to get there. Both depend heavily on inflation. At 6% inflation, expenses of 50,000 a month today become about 2.87 lakh a month in 30 years, and those expenses keep rising every year you are retired, so the target corpus is much larger than most people expect.

The calculator first inflates your current monthly expenses to the retirement year. It then values a stream of yearly withdrawals that grow with inflation and are funded by a corpus earning your post-retirement return, using the growing-annuity formula Corpus = E × [1 − ((1 + g)/(1 + r))^N] ÷ (r − g) × (1 + r). Your existing savings and monthly investments are projected at the pre-retirement return, and any shortfall is converted into an additional monthly investment. The result is an estimate built on constant rates, not a forecast.

How to use Retirement Calculator

1. Enter your current age, the age you want to retire at and the age to plan until.
2. Enter your current monthly expenses in today’s money, leaving out costs such as EMIs that will end before retirement.
3. Set the expected inflation rate.
4. Enter the expected return before retirement and a lower, safer return after retirement.
5. Add your current retirement savings and the amount you already invest each month.
6. Read the corpus needed, your projected savings and the additional monthly investment, and review the drawdown table.

Tips for better results

• Plan until at least 85 or 90; running out of money at 80 is a far bigger problem than leaving some behind.
• Use a post-retirement return one to three points lower than before retirement, because portfolios usually become more conservative.
• Healthcare costs tend to rise faster than general inflation, so keep a separate health fund or adequate insurance.
• Revisit the plan every year or two as your income, expenses and savings change.

Common use cases

• Setting a retirement target number for the first time.
• Checking whether current EPF, NPS and SIP contributions are enough.
• Testing the impact of retiring five years earlier or later.
• Explaining to a partner how inflation changes the amount you need.

Common mistakes to avoid

• Ignoring inflation and planning for today’s expenses at retirement.
• Assuming equity-like returns for the whole retirement period.
• Leaving out existing savings that are earmarked for other goals, which overstates progress.