Equity Optimization Calculator
Two questions, one page. The Time to target tab answers how long your equity takes to grow from its current value to a target at a steady annual growth rate, with projected values at 5, 10, 15, and 20 years. The ROE gap tab measures the distance between your actual performance and your target return on equity: the optimization gap in dollars.
Assumes a constant growth rate. Real returns vary; treat the projection as a planning estimate.
Quick Answer
Time to target: $100,000 growing to $500,000 at 15% a year takes 11.52 years: ln(500,000 ÷ 100,000) ÷ ln(1.15) = 1.6094 ÷ 0.1398. Projections: $201,136 after 5 years, $404,556 after 10, $1,636,654 after 20. ROE gap: $2,000,000 of equity with an 18% target ROE needs $360,000 of income; actual net income of $250,000 leaves a $110,000 shortfall (actual ROE 12.5%).
Worked examples, checked against this exact tool
Time to target: $100,000 growing to $500,000 at 15% a year takes 11.52 years: ln(500,000 ÷ 100,000) ÷ ln(1.15) = 1.6094 ÷ 0.1398. Projections: $201,136 after 5 years, $404,556 after 10, $1,636,654 after 20. ROE gap: $2,000,000 of equity with an 18% target ROE needs $360,000 of income; actual net income of $250,000 leaves a $110,000 shortfall (actual ROE 12.5%).
The time-to-target formula
Compound growth says target = current × (1 + g)t. Solving for t: t = ln(target ÷ current) ÷ ln(1 + g). The logarithm base does not matter as long as it is the same top and bottom: natural log and base-10 both give 11.52 years in the example. (An earlier version of this page mixed ln on top with base-10 on the bottom and printed 26.38 years: the tool always computed 11.52, and the text is now corrected.) A quick sanity check: the rule of 72 says money doubles every ~4.8 years at 15%, and $100k needs about 2.3 doublings to reach $500k: 2.3 × 4.8 ≈ 11 years.
The ROE optimization gap
Gap = (Target ROE × Total equity) − Actual net income. A positive gap is the income shortfall to close: the business is under-earning its equity base. A negative gap means performance already exceeds the target. The gap turns a vague “improve ROE” goal into a dollar number: $110,000 more income, or the equivalent equity reduction, to hit 18%[2]. To decompose ROE into margin, turnover, and leverage, see the DuPont breakdown[7].
What equity means here
Equity is ownership value with growth potential: company shares, a business’s book equity, an investment portfolio, or property equity. The time-to-target tab fits anything with a projected steady growth rate; the ROE tab fits businesses measured on return on equity. The equity growth calculator projects the growth path alone, and the advisor equity calculator values equity stakes. For home-equity borrowing questions, see our equity home calculator, which handles loan-to-value limits instead.
What competing calculators miss
Rival pages each own one interpretation: time-to-target here, ROE gap at bravecalculator, portfolio allocation at calculatorultra, home equity at savvycalculator. None combine them. This page runs the two business interpretations side by side, adds the projection snapshots and target year the formula-only pages skip, and carries the corrected worked example.
Frequently asked questions
t = ln(target ÷ current) ÷ ln(1 + g). $100k to $500k at 15% takes 11.52 years.
(Target ROE × total equity) − actual net income: the dollar shortfall (or surplus) against your return-on-equity goal.
The business is under-earning: that many more dollars of net income are needed to hit the target ROE.
Performance already exceeds the target: actual income is higher than the target ROE requires.
It depends on the asset: broad markets have averaged around 7–10% long-term; high-growth companies or sectors can exceed 15%, with more volatility.
It is exact for a constant rate and an estimate for the real world: markets fluctuate, companies dilute, and property values cycle.
Yes: plug your portfolio value, your retirement target, and an assumed return to test whether the timeline fits.
Yes for the growth tab, as long as you can project a growth rate; the ROE tab suits operating businesses.
The tool tells you the target is already reached rather than printing a negative time.
No, as long as numerator and denominator use the same base. Mixing bases (as an earlier version of this page did) gives a wrong answer.
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References
[1] Corporate Finance Institute. "Time Value of Money" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
[2] Wall Street Prep. "Return on Equity (ROE)" wallstreetprep.com (Accessed Oct 17, 2026).
[3] Corporate Finance Institute. "CAPM: Capital Asset Pricing Model" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
[4] Corporate Finance Institute. "Financial Ratios" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
[5] Corporate Finance Institute. "DuPont Analysis" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
[6] Corporate Finance Institute. "Rule of 72" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
[7] Charles Schwab. "The Power of Compounding" schwab.com (Accessed Oct 17, 2026).
[8] Corporate Finance Institute. "Equity Ratio" corporatefinanceinstitute.com (Accessed Oct 17, 2026).
