How much should I invest each month?
There is no universal figure, but there is a method: fund the essentials first, then invest a fixed percentage of income automatically. The calculator shows what any given monthly amount becomes under three market scenarios.
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A workable order of operations
Clear high-interest debt, build a small emergency buffer, capture any employer retirement match in full, then invest a set percentage of income. Ten to fifteen percent is a common target; twenty or more accelerates things considerably.
Percentages beat fixed amounts because they rise automatically with income, which is the simplest defence against lifestyle inflation.
Plan on the weak scenario
The second chart shows the same contribution under stronger and weaker markets. The gap between them over a long horizon is usually larger than the total you contribute.
Build the plan so it still works on the lower line. Anything above that is a bonus rather than a requirement.
Frequently asked questions
What percentage of income should I invest?
Ten to fifteen percent is a common guideline for a conventional retirement age. Earlier retirement needs considerably more.
Should I invest or pay off my mortgage?
Compare the mortgage rate with your realistic after-tax return. Paying down debt is certain; investment returns are not.
Is it too late to start at 40?
No. Twenty-five years is a long compounding runway - the projection above shows what that looks like.
How do fees change the answer?
The insight panel shows what one percentage point of annual cost removes from your result. Over decades it is usually a large number.
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