Retirement Calculator

Retirement planning is two calculations chained together: how large a pot your contributions will build, and how long that pot survives your withdrawals. This tool joins them so you can see whether a plan holds up rather than just admiring a corpus figure.

Inputs

Current age

Retirement age

Current savings

Monthly saving

Return(%)

Result

43,826,018.56

Corpus available after 30 years of saving

How the retirement calculator works

Accumulation uses the future value of a growing series: each monthly contribution compounds at i = annual return ÷ 12 for the months remaining until you stop working.

Drawdown reverses it. A sustainable annual withdrawal is often approximated as 4% of the starting corpus, adjusted for inflation each year — a rule of thumb derived from historical market sequences, not a guarantee.

Target corpus ≈ annual spending in retirement ÷ withdrawal rate. Spending 40,000 a year at a 4% rate implies roughly 1,000,000.

Worked example: age 35, retiring at 60

Current savings 200,000, contributing 1,200 a month, assumed 8% return.
Existing savings grow to 200,000 × 1.08^25 ≈ 1,370,000.
Contributions: 1,200 × [((1 + 0.00667)^300 − 1) ÷ 0.00667] ≈ 1,140,000.
Projected corpus ≈ 2,510,000. At a 4% withdrawal rate that supports about 100,400 in the first year.
Adjusted for 3% inflation over 25 years, that 100,400 buys what roughly 48,000 buys today — the check most projections skip.

Common mistakes to avoid

Comparing future money to today's prices

A seven-figure corpus in 2050 is not a seven-figure lifestyle. Either inflate your spending target or discount the corpus, but do one of them.

Using the same return before and after retiring

Portfolios usually shift toward bonds near retirement, lowering expected returns. Modelling 8% through a 30-year drawdown overstates safety.

Ignoring sequence-of-returns risk

A poor market in the first few retirement years does far more damage than the same market later, because withdrawals are taken from a shrinking base.

Frequently asked questions

How much do I need to retire?

Start from spending, not from a headline number. Annual retirement spending divided by a withdrawal rate of 3.5–4% gives a defensible target.

Is the 4% rule still valid?

It remains a reasonable planning anchor, but it came from a specific historical dataset and a 30-year horizon. Longer retirements or lower expected returns argue for 3–3.5%.