Get a simple, transparent starting point for splitting your money between stocks, bonds and cash. The calculator starts from the rule of 100, 110 or 120 minus your age, adjusts for your risk tolerance and limits stocks when you need the money soon. Educational only, not personal financial advice.
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About you
years
years
Portfolio
$
%
Part of the stock slice held outside your home market; 0 to skip.
%
Optional. Leave blank to use the horizon-based cash level.
Enter your values to see the result.
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How to use the Asset Allocation Calculator
Enter your age and how many years until you need the money.
Pick a risk tolerance and the starting rule (100, 110 or 120 minus age).
Enter the amount to invest and, if you like, an international share and a minimum cash level.
Press Calculate to see the mix, the dollar amounts, the chart and how the mix shifts as you age.
How the suggested mix is built
Base stocks = rule number − age (100, 110 or 120).
Risk adjustment: conservative −10 points, moderate 0, aggressive +10 points; then kept between 0% and 100%.
Horizon cap on stocks: under 3 years 20%, under 5 years 40%, under 10 years 60%, under 15 years 80%, otherwise no cap.
Cash: under 3 years 30%, under 5 years 15%, under 10 years 10%, otherwise 5% (conservative +5, aggressive −5, never below your minimum).
Bonds = whatever is left: 100 − stocks − cash.
The steps are deliberately simple so you can see exactly where each number comes from and change the inputs to match your own view.
Rule of 100 vs. 110 vs. 120 (moderate risk, long horizon)
Age
Rule of 100 stocks
Rule of 110 stocks
Rule of 120 stocks
25
75%
85%
95%
35
65%
75%
85%
45
55%
65%
75%
55
45%
55%
65%
65
35%
45%
55%
75
25%
35%
45%
The rest goes to bonds and cash. With a 30-year horizon and moderate risk, a 35-year-old using the rule of 110 gets 75% stocks, 20% bonds and 5% cash.
What each asset class does
Stocks offer the highest long-run growth potential but can drop 30–50% in a bad year.
Bonds pay interest and usually swing less, cushioning a portfolio when stocks fall.
Cash (savings accounts, money market funds, Treasury bills) is stable and available, but may not keep up with inflation over long periods.
International stocks spread risk across economies and currencies; many diversified portfolios hold 20–40% of their stocks abroad.
Frequently asked questions
What is the rule of 110?
It is a rule of thumb that says the percentage of your portfolio in stocks should be about 110 minus your age. A 40-year-old would hold about 70% stocks and 30% bonds and cash. The older rule of 100 is more conservative and the rule of 120 more aggressive, reflecting longer life spans and lower bond yields.
How does this calculator adjust for risk tolerance?
Conservative removes 10 percentage points from stocks and adds 5 points of cash; aggressive adds 10 points to stocks and trims cash by 5 points. Moderate uses the rule unchanged. The result is then kept between 0% and 100%.
Why does a short time horizon lower the stock share?
Stocks can fall sharply and take years to recover, so money needed soon is usually kept in steadier assets. Here stocks are capped at 20% for horizons under 3 years, 40% under 5, 60% under 10 and 80% under 15 years, with no cap beyond that.
How much cash should I hold?
This calculator sets aside 30% cash for horizons under 3 years, 15% under 5, 10% under 10 and 5% for longer horizons, before the risk adjustment. Many people also keep a separate emergency fund of several months of expenses outside their investment portfolio.
What is a glide path?
It is the way an allocation shifts from stocks toward bonds and cash as you get older and your goal gets closer. Target-date funds follow a glide path automatically; the table shows the path this simple rule produces.
How often should I rebalance?
A common approach is once a year, or whenever an asset class drifts more than about 5 percentage points from its target. Use a portfolio rebalancing calculator to work out the trades.
Is this the right allocation for me?
It is only a starting point. Your income stability, pensions, debts, other savings, taxes and how you react to market drops all matter. Consider talking to a qualified financial professional before making big changes.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.