Asset Allocation Calculator

Suggest a stock and bond split based on age and risk tolerance.

Please note: For information only, not investment advice. Projections assume constant rates; real markets fluctuate and capital is at risk.

What the Asset Allocation Calculator does

Age-based allocation reduces equity exposure as retirement approaches, on the reasoning that a long horizon lets you ride out downturns while a short one does not. The rule is a starting point — the right allocation is one you can hold through a bear market without selling.

Formula

Stock % = 120 − Age, adjusted for risk tolerance
Aggressive: +10 points · Conservative: −15 points
Bond % = 100 − Stock %

Inputs explained

Input	Unit	Required	Notes
Your age	number	Yes	Accepts 18 or more, up to 100.
Risk tolerance	one of 3 options	Yes	—
Target retirement age	number	Yes	Accepts 30 or more, up to 100.
Portfolio value	selected currency	Optional	Accepts 0 or more.
Currency	one of 10 options	Optional	—

How to use it

Choose Risk tolerance and Currency.
Enter Your age and Target retirement age.
Optionally add Portfolio value.
Select Calculate.

Worked example

A 35-year-old with moderate risk tolerance retiring at 65.

Age: 35
Risk: Moderate
Retirement: 65

120 − 35 = 85% stocks and 15% bonds, with 30 years to retirement.

Frequently asked questions

Is this rule reliable?

It is a reasonable default, not a prescription. Someone with a secure pension can take more equity risk than the rule suggests; someone dependent on the portfolio for near-term income should take less.

What about other asset classes?

Property, commodities and cash all have a place. Treat the stock/bond split as the core decision and layer other assets on top.

Method and sources

Method. A widely repeated age heuristic — equity share ≈ 120 minus age — shifted up or down by the risk tolerance selected.

Assumptions

Age stands in for investment horizon, which holds only if retirement is the goal and the money is untouched until then.

Limitations

This is a rule of thumb with no empirical basis, not a recommendation. The constant has drifted upward over the years — 100, then 110, then 120 — as life expectancy and market assumptions changed, which is itself evidence that no particular number is established.
It ignores everything that actually determines a suitable allocation: other income, job security, existing wealth, liabilities, tax position, and whether the investor can hold the allocation through a severe fall without selling.
The allocation somebody can live with in a bear market matters more than the one an arithmetic rule produces, because the cost of abandoning a plan at the bottom dwarfs the difference between any two sensible splits.