Dividend Calculator – Dividend Reinvestment (DRIP)
Projects how a dividend portfolio grows when payouts are reinvested (DRIP). Enter your initial investment, dividend yield, payout frequency, growth rates, extra contributions and dividend tax to see the final value, share count, future dividend income and yield on cost.
Project Dividend Income and Growth with Reinvestment
Dividend Reinvestment (DRIP) Formula
Where:
- \(V_n\) — portfolio value at the end of payout period \(n\) (one period = the interval between two payouts)
- \(C_n\) — additional contribution added at the start of the period
- \(P_n\) — share price at the end of period \(n\)
- \(d_y\) — dividend per share for each payout in year \(y\)
- \(D_0\) — initial annual dividend per share (share price × yield, or entered directly in dollars)
- \(t\) — dividend tax rate, as a decimal (e.g. 0.15 for 15%)
- \(m\) — payouts per year: 12 (monthly), 4 (quarterly), 2 (semi-annual) or 1 (annual)
- \(g_d\), \(g_p\) — assumed dividend growth and share price growth per year, in %
The fraction says: your existing value plus the new contribution buys shares at the start-of-period price \(P_{n-1}\); by the end of the period those shares are worth the new price \(P_n\) plus the after-tax dividend, which is immediately reinvested. If DRIP is switched off, the term \((1-t)d_y\) is dropped and the after-tax dividend accumulates as cash instead.
Dividend Reinvestment – Calculation Example
Example: you invest $10,000 in a stock trading at $50 per share with a 3.5% dividend yield paid quarterly. You expect the dividend to grow 5% per year and the share price 4% per year, you add $100 per month, dividends are taxed at 15%, and they are reinvested (DRIP) for 20 years.
You start with \(10{,}000/50 = 200\) shares. The annual dividend is \(50 \times 0.035 = \$1.75\) per share, or \(1.75/4 = \$0.4375\) per quarter — \(\$0.3719\) after tax, which buys roughly 1.5 extra shares on top of the $300 (three monthly contributions) added each period. Each payout the snowball grows: more shares, a bigger dividend, more shares again.
\[ V_{\text{20 years}} \approx \$95{,}300, \qquad S_N = \frac{V_N}{P_N} \approx \frac{95{,}300}{50 \times 1.04^{20}} \approx 870 \text{ shares} \]
Result: about $95,300 in ~870 shares, generating roughly $3,750 of dividend income in the final year — a yield on cost of about 11% on the $34,000 actually invested (\(10{,}000 + 100 \times 12 \times 20\)), with around $33,000 in total dividends received along the way.
How to use the calculator
- Enter your Initial investment and the current Share price — together they set your starting number of shares.
- Enter the Dividend rate and pick the Basis: either "% yield per year" (a percentage of the share price) or "$ per share per year
Frequently Asked Questions
Does dividend reinvestment (DRIP) really make a big difference over just keeping dividends as cash?
Yes, over long horizons the difference compounds substantially. Reinvested dividends buy extra shares, and those shares pay dividends themselves, creating a snowball effect. With a 3–4% yield growing 5% per year, DRIP can add tens of percent to your final value over 20 years, and more over 30–40. You can see the exact gap by running the calculator once with the DRIP checkbox on and once off and comparing the results.
What is yield on cost and why does it get so high in the results?
Yield on cost is the annual dividend income in the final year divided by the total money you actually invested. It grows because the dividend per share rises over time while your cost basis stays fixed, and because reinvestment adds shares without new money from you. A stock bought at a 3.5% yield that raises its payout 5% per year reaches roughly an 11% yield on cost after 20 years — that's normal, not an error.
How is this dividend calculation different from compound interest?
Compound Interest assumes fixed periodic growth of one lump sum. Here two things grow independently: the share price and the dividend per share, and the dividend is calculated per share, not on the total value. Reinvested dividends buy shares at the current (rising) price, so the effective compounding rate changes every period. It's a share-based model, which is why the output includes a share count.
Should I enter the dividend yield or the dividend dollars per share?
Either works — use the Basis selector to switch. If you enter a yield, the calculator converts it to dollars per share by multiplying the share price by the yield percentage (e.g., $50 × 3.5% = $1.75 per year). Many stock quote sites quote dividends in dollars per share per year; in that case pick that basis directly. The key is not to mix them up, or your income will be off by orders of magnitude.
How does the dividend tax rate affect the projection?
Dividends are taxed when paid, and only the after-tax amount buys shares when DRIP is on. A 15% tax rate means a $0.4375 quarterly payout reinvests only $0.3719 per share, so you accumulate shares slightly slower and lose the compounding on that difference forever. Over decades this compounds meaningfully — set the rate to 0 to compare a tax-advantaged account like an IRA or ISA against a taxable brokerage.
What are realistic values for dividend yield and dividend growth?
Mature US dividend payers typically yield 2–5% with 5–10% annual dividend growth; REITs and MLPs yield more but grow more slowly. The payout ratio (dividends divided by earnings) above roughly 80% makes sustained growth questionable. Very high yields (8%+) often signal a distressed company that may cut its dividend. These are assumptions, not guarantees — even long-standing payers have frozen or reduced dividends in past crises. Treat the output as a scenario, not a prediction.
Why does payout frequency barely change the final value?
With DRIP on, the frequency mainly affects how quickly dividends get reinvested. Monthly payouts reinvest slightly sooner than annual ones, so they compound a touch faster, but the total dividends paid per year are the same expressed as an annual amount. The bigger impact is on the contribution schedule: contributions are aligned to payout periods, so with annual payouts a '$100 per month' contribution effectively arrives as one $1,200 lump each year instead of monthly increments.