b2KIT

Asset Allocation Calculator

Design and rebalance investment portfolios across stocks, bonds, and alternatives based on risk tolerance, age, and goals.

Tested tool guide Tested browser tools Checked August 15, 2026

What Asset Allocation Calculator does and how it behaves

This tool turns a risk-tolerance rating, your age, and a stated goal or time horizon into a target split across stocks, bonds, and alternatives, then compares that target against what you currently hold so you can see the rebalancing gap in each bucket. It runs on a rule-of-thumb heuristic, not a personalized financial plan. The thing people get wrong most often: they treat "alternatives" as one uniform, moderate-risk category, when the label can cover anything from a REIT fund to commodities to private equity, each with a very different risk and liquidity profile than the others.

How the result is produced

1

Target split from inputs

Risk tolerance (conservative, moderate, aggressive), age, and a stated goal or horizon feed a rule-of-thumb formula that outputs a percentage target for stocks, bonds, and alternatives. Shorter horizons and lower risk tolerance shift weight toward bonds; longer horizons and higher risk tolerance shift weight toward stocks. The exact split moves with whichever inputs you select rather than following one fixed ratio.

2

Rebalancing gap

Enter current holdings by dollar amount or percentage in each bucket, and the calculator subtracts your current split from the target split to flag which buckets are overweight and which are underweight, shown as a percentage or dollar move. It does not factor in trading costs, the tax consequences of selling appreciated positions, or account minimums.

Good uses

  • Deciding a starting stock/bond/alternatives mix when opening a new IRA or brokerage account
  • Checking how far a portfolio has drifted from target after stocks outperform bonds for a stretch
  • Seeing how the recommended mix shifts when you plug in a later retirement age or shorter horizon

Limits and checks

  • "Alternatives" is treated as one bucket, but a REIT fund, commodities, and private equity carry very different risk and liquidity profiles lumped under that single label
  • The rebalancing gap ignores taxes and trading costs, so following it literally in a taxable account can trigger capital gains you didn't plan for
  • The target split is a generic rule tied to age and risk tolerance, not a plan that accounts for debt, employer stock concentration, or other accounts you hold elsewhere

Common questions

Does it treat tax-advantaged and taxable accounts differently?

No. It treats everything you enter as one combined pool, so it won't tell you which asset class to hold in an IRA versus a taxable brokerage account for tax efficiency. You have to apply that layer yourself.

Is the target allocation it recommends the right one for me?

Not necessarily. It applies a general rule of thumb based on risk tolerance and age, the kind of starting point many advisors use, but it doesn't know your full financial picture. Treat the output as a baseline to adjust, not a final answer.

References and verification

The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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