A method that you can repeat yourself.
Estimate expenses
Take today’s monthly expense and multiply by the share you will still need.
Inflate to retirement age
Grow it at an assumed inflation rate until you retire.
Estimate the years of income
Plan to a ripe age such as 85–90.
Work backwards
Find the corpus that can fund those years at a sensible return.
Key takeaway. Run the numbers in our calculator and revisit yearly.
General information only; not personal advice. Rules and limits change, so verify current details. Last updated October 2026.