Investment & Retirement Calculators · USA

Portfolio Allocation Calculator USA: Drift & Scenario Comparison

Compare a current stock, bond, cash and other mix with a transparent educational comparison mix. Explore percentage and dollar drift across scenarios without treating the model mix as a personalized investment recommendation.

AllocationFit™ Scenario Comparison Engine
Current mix Stocks · Bonds · Cash · Other
Comparison model Risk · Horizon · Goal
Drift Percent + dollars
Scenario signal What changes most
Calculation review Oleksandr Domchynskyi Method Calculation methodology Last reviewed August 9, 2026 Official sources 4 page-specific references Corrections Report an issue
See the AllocationFit™ formula, comparison constants and model boundaries

How percentages become dollar drift

  1. The current mix must total 99.5%–100.5%; a near-total is normalized to exactly 100%.
  2. asset dollars = portfolio value × asset percentage / 100
  3. percentage drift = current percentage − target percentage
  4. dollar drift = current dollars − target dollars
  5. comparison drift dollars = sum of absolute dollar drift / 2, so an overweight and the matching underweight are not counted twice.
  6. Displayed dollars round to the nearest dollar; internal asset and drift math retains cents or additional percentage precision where required.

Internal comparison mix and score constants

Model version: NH-PA-US-2026.08b. Source review: August 9, 2026.

Base risk mixes, Stocks/Bonds/Cash/Other: Conservative 35/45/15/5; Moderate 60/30/5/5; Growth 75/17/3/5; Aggressive 85/10/2/3.

Horizon controls: 0–2 years caps stocks at 25% and tests for at least 65% bonds plus cash; 3–5 years uses 50% and 45%; 6–10 years uses 75% and 20%; 10+ years uses 90% and 8%.

Goal adjustments: Home/large purchase subtracts 20 points from stocks and adds 10 each to bonds and cash; income stability subtracts 15 from stocks, adds 12 to bonds and 3 to cash; wealth growth adds 10 to stocks, subtracts 7 from bonds and 3 from cash. Retirement and general investing add no adjustment.

Alignment score: starts at 100. Total absolute drift is multiplied by 1.2. Largest-drift penalties are 8 points at the selected threshold, 15 at 10 points and 25 at 15 points. Horizon/equity penalties are 25 for short-horizon stocks above 40%, 18 for medium-horizon stocks above 65%, and 15 for Conservative stocks above 60%. Long-horizon excess cash is multiplied by 1.1 and capped at 20; the stability gap is multiplied by 1.2 and capped at 22. Concentration penalties are 8/15/25 at 10%/15%/25%; an Other bucket of 15%/20% adds 7/12; a user-defined target subtracts 4. The final score is rounded and clamped to 0–100.

Score bands: 85–100 strong alignment; 70–84 mostly aligned; 55–69 review recommended; 35–54 high mismatch; 0–34 correct the mix first. These constants are a NumeraHub educational heuristic, not an official standard or suitability score.

Included and deliberately excluded

Included: four asset-class percentages and dollars, internal or user-defined comparison mix, drift, comparison drift dollars, editable drift threshold, cash drag, stability gap, single-position and sector concentration checks, six comparison paths and two explanatory charts.

Not included: security selection, expected return, future performance, fund fees, capital-gains tax, transaction costs, bid-ask spreads, account type, tax-loss harvesting, liquidity inside the Other bucket, or a regulated suitability assessment.

Practical limit: a mathematically cleaner mix can still be the wrong action when taxes, fees, liquidity needs or the target itself have not been reviewed.

What the official references support

These references support the educational boundaries and definitions. They do not prescribe NumeraHub’s comparison percentages, 5-point default threshold, alignment score or stress cases.

Current mix & planning profile

Enter the allocation and the purpose of the money

Core inputs

Portfolio size

Start with the current portfolio value. The calculator converts each allocation percentage into dollars.

$
Use the investment portfolio you want to review, not your entire net worth.

Current allocation

Enter the asset-class mix as percentages. A total close to 100% can be normalized; a larger mismatch must be corrected.

Total 100%
%
U.S. and international stock funds or individual stocks.
%
Bond funds, Treasury exposure, fixed-income holdings.
%
Cash, money market funds or short-term reserves inside this portfolio.
%
Alternatives, REITs, commodities or other holdings that do not fit the first three buckets.
Allocation total is ready. The current mix equals 100%.

Planning profile

The target allocation is based on the selected horizon, risk comfort and goal. It is a planning heuristic, not a recommendation.

The internal model applies a stronger bond-and-cash stability check to shorter horizons.
Risk comfort affects the stock/bond/cash target mix.
The same allocation can be fine for one goal and risky for another.
%
The editable 5-point default is a NumeraHub planning assumption, not an official rebalancing rule.

Market movement can create allocation drift without a new trade.

A high stock mix can be reasonable long term but dangerous for near-term goals.

Several funds do not always mean true diversification if the holdings overlap.

Advanced review options Optional checks for concentration, stock split and user-defined targets.

Concentration checks

Asset-class allocation can look balanced while one position or sector still carries too much risk.

%
Optional. Use 0 if no single stock, fund or holding dominates.
%
Optional. Helpful when several funds overlap in the same sector.

Stock mix detail

This does not change the main stock allocation. It helps explain whether stock exposure is mostly U.S., international or unclear.

%
Optional share of the stock bucket, not the whole portfolio.
%
Optional share of the stock bucket. U.S. + international should equal 100%.

User-defined target

Use this only when you already have a target allocation. The engine will check drift and risk signals, not confirm suitability.

%
%
%
%
Custom target is off. AllocationFit™ will use the planning heuristic.
Scenario comparison

Your current mix versus an educational comparison mix

Ready to compare
Educational comparison preview No personalized recommendation
No result yet

Calculate to compare the entered mix with a model scenario

The calculator will show how the entered allocation differs from a transparent model comparison mix. The comparison is educational: it does not tell the user what to buy, sell, hold or rebalance.

What the comparison will show Current mix ↔ model mix

After a valid Calculate, the page can show percentage drift, dollar drift, model alignment and scenario stress tests.

Current mix Entered by user Model mix Educational heuristic Drift Percent + dollars Purpose Scenario comparison
Current allocationInputWhat is entered
Comparison allocationModelNot a recommendation
Largest differenceDriftShown after Calculate
Model alignmentScoreEducational heuristic
What it means

A larger drift means the entered mix differs more from the selected comparison assumptions. It does not mean a trade is required.

Important boundary

Taxes, fees, account type, specific holdings, liquidity needs and suitability are outside this model and can materially change a real-world decision.

Educational use

Use the result to compare scenarios and understand model sensitivity. Treat the comparison mix as a reference assumption, not as a portfolio prescription.

Nothing is calculated yet. Results, table, scenarios, charts, sticky summary and XLSX export stay hidden until a valid Calculate.

Three-step drift check

Read drift before changing the portfolio

1. Enter the current mix

Use the portfolio you want to review. Keep emergency savings separate unless that cash is intentionally part of the investment portfolio.

2. Pick the planning profile

Choose the time horizon, risk comfort and goal that match the money’s purpose. A near-term home fund should not be judged like a 25-year retirement portfolio.

3. Review the largest mismatch

Start with the biggest drift or strongest risk flag. Small allocation differences matter less than a major stock overweight, cash drag or concentration issue.

Drift interpretation

Why the largest allocation gap matters more than portfolio size

The result is a planning review, not a command to trade. A portfolio can be technically diversified and still poorly aligned with the money’s purpose. A 75% stock allocation may be reasonable for a long-horizon retirement account, but it can be too exposed for money needed in the next two years. A 30% cash position can protect a short-term goal, but the same cash level can drag on a long-term growth plan.

AllocationFit™ focuses on the gap between your current mix and the selected planning profile. Portfolio value sets the dollar scale, while the largest drift identifies the first mismatch to verify.

Read the comparison signal

Understand what drives the scenario difference

If the allocation total is wrong

Fix the inputs before relying on any verdict. A portfolio mix below or above 100% changes every dollar calculation.

If stock exposure is the warning

Check the time horizon first. The same stock percentage can be acceptable for long-term wealth building and risky for a near-term spending goal.

If cash drag is the warning

Decide whether the cash is intentional. Cash reserved for a near-term goal is different from idle cash sitting inside a long-term investment account.

If drift is the warning

Review the largest overweight and underweight together. In this model, both sides form one review amount rather than two separate trades.

Risk, horizon and rebalancing

Why time horizon changes the meaning of risk

Time horizon is the pressure point in allocation planning. Money needed soon has less room to recover from market volatility. Investor.gov notes that a longer horizon may support greater comfort with volatile investments; the internal model therefore permits a higher stock cap, while real loss tolerance and liquidity needs still require a separate review.

Rebalancing is not about predicting the market. It is a discipline for bringing the portfolio back toward the selected asset mix when market movement changes the risk profile. A stock-market run-up can quietly turn a moderate portfolio into a growth-heavy portfolio without any new contributions.

Reconciled portfolio cases

Three situations where allocation drift matters

$120,000 · long horizon · 28% cash

Long-term profile with $27,600 of cash drift

Current mix 50/17/28/5, Moderate risk, 10+ years and a retirement goal produces the internal 60/30/5/5 comparison mix. Cash is 23 points, or $27,600, above the model reference. The model returns 0/100, indicating a very large mismatch within this educational scenario.

Scenario takeaway: the result shows how strongly the cash assumption changes the model comparison; it does not prescribe where the cash should be held.
$80,000 · 0–2 years · 70% stocks

Near-term home fund with $44,000 of stock drift

Current mix 70/15/10/5, Conservative risk and a home-purchase goal produces a 15/55/25/5 internal target. Stocks are 55 points, or $44,000, above target. The score is 0/100 and time-horizon equity pressure becomes the verdict.

Scenario takeaway: the short-horizon assumptions make stock exposure the dominant model signal; suitability still requires information outside this calculator.
$200,000 · long horizon · 74% stocks

A stock run-up creates a $28,000 review amount

Current mix 74/16/5/5 against the Moderate 60/30/5/5 comparison mix puts stocks 14 points, or $28,000, above the model reference and bonds the same amount below. The score is 51/100, which the model labels as a meaningful mismatch.

Scenario takeaway: market gains can change the mix even when no new trade caused the drift.
Allocation decision traps

Four mistakes that weaken allocation decisions

01

Treating a generic rule as personal advice

Rules of thumb can be useful starting points, but they do not know the investor’s cash needs, job stability, tax situation or emotional tolerance for losses.

Use the rule as a comparison point, not the final answer.
02

Ignoring time horizon

Stock exposure means different things when the money is needed in one year versus twenty years. The result should be judged against the goal date.

Match the portfolio risk to when the money may be needed.
03

Letting gains silently change the risk level

A rising market can push stocks far above target. The portfolio may feel successful while becoming more aggressive than intended.

Review drift periodically instead of only after a market decline.
04

Assuming several funds means true diversification

Multiple funds can still hold many of the same companies or sectors. Concentration can hide inside funds, not only individual stocks.

Look through overlapping holdings when one sector or company dominates.
AllocationFit math

How percentages become comparison drift and drift dollars

AllocationFit™ first checks whether the current asset-class percentages reconcile to 100%. Totals from 99.5% through 100.5% can be normalized. A larger mismatch pauses the decision because the current mix is not internally consistent.

The engine then converts each percentage into dollars, builds a planning target from the selected risk comfort, time horizon and goal, and compares current dollars with target dollars. Drift is shown both as a percentage and as a dollar amount. The estimated rebalance amount uses half of the total absolute dollar drift, because moving money out of one overweight asset class and into an underweight class is one review action, not two separate portfolio totals.

The alignment score is a bounded educational heuristic. It considers total drift, largest single drift, short-horizon stock exposure, cash drag, stability gap, concentration inputs and unclear “Other” exposure. It is not a suitability score, risk questionnaire, portfolio optimization model or prediction of future returns.

Model boundary

What AllocationFit measures and where the estimate stops

Version and source review

NH-PA-US-2026.08b; official references reviewed August 9, 2026.

Included

Current and target mix, asset dollars, percentage and dollar drift, review amount, editable threshold, concentration, cash-drag, stability-gap, scenario, chart and export outputs.

Excluded

Expected return, security selection, fund fees, capital-gains tax, transaction costs, account type, tax-loss harvesting, liquidity analysis, Monte Carlo simulation and regulated suitability review.

Evidence boundary and source set

The four official references support the definitions and warnings, not the internal target percentages or score: Investor.gov asset allocation, Investor.gov rebalancing, FINRA diversification and FINRA concentration risk.

Educational planning estimate — not investment, tax, legal or financial advice. Review the calculation methodology or report a model issue. The target and score are internal comparison tools, not official or personalized recommendations.

Before acting on the drift

Portfolio allocation questions

Seven formula, target, rebalancing and limitation checks to read before relying on the estimate.