Project compound interest maturity by frequency and work out CAGR from a start and end value. See interest earned, growth multiple and annualized rate offline.
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Frequency sets how often interest rejoins the principal: yearly uses 1, half-yearly 2, quarterly 4 and monthly 12. More frequent compounding lifts the maturity slightly at the same rate. For example, Rs 50,000 at 8% over 10 years ends higher with monthly rests than with yearly ones. Compare both settings in the tool and see /terms.
CAGR = (end ÷ start)^(1 ÷ years) − 1, with the growth multiple equal to end ÷ start and the absolute gain equal to end − start. For example, $10,000 growing to $20,000 over five years gives about 14.87% CAGR, a 2x multiple and a $10,000 gain. It smooths a bumpy path into one steady yearly pace for comparison.
Compound interest projects forward from a principal, a rate and a compounding frequency to a future amount. CAGR runs the other way: given a start and end value, it reports the single steady rate that would connect them. Use compound interest to forecast a balance, and CAGR to benchmark a past return or a revenue line against other horizons.
Duration magnifies the base. $10,000 at 21.6% for three years reaches $18,000 for an $8,000 gain, while 14.87% over five years reaches $20,000 for a $10,000 gain. The shorter sprint shows the hotter rate but the smaller harvest, so always read CAGR alongside the absolute multiple.
It is educational projection only, never investment advice. Fees, taxes, inflation and market risk are excluded, so an 8% projection can differ widely from realized returns. Everything runs on the device, so principals, rates and values never upload, and closing the tab clears them. Consult a professional and see /terms.
CAGR assumes a single start-to-end path, so it fits lump sums and revenue comparisons. Installments at varying prices break that assumption, and XIRR weights each cash flow by timing instead. A monthly SIP near 13.2% XIRR can show a naive 14.87% CAGR, so use CAGR for lump sums and XIRR for contributions. Compare methods with the SIP calculator.
Two linked views cover growth both ways. Compound interest projects forward from a principal at a chosen compounding frequency to a maturity amount and interest earned; CAGR runs in reverse, turning a start and end value over a number of years into a single steady yearly rate, a growth multiple and an absolute gain. The compound view supports a currency selector and yearly, half-yearly, quarterly or monthly rests, while the CAGR view is unit-agnostic. Example: Rs 50,000 at 8% for 10 years grows further on monthly rests than yearly ones, and $10,000 reaching $20,000 over five years reports about 14.87% CAGR on the other tab.
Compound maturity is principal × (1 + rate ÷ frequency)^(frequency × years), so faster compounding raises the result slightly at the same nominal rate. CAGR is (end ÷ start)^(1 ÷ years) − 1, the multiple is end ÷ start and the gain is end − start. Reference table: yearly uses frequency 1 | half-yearly 2 | quarterly 4 | monthly 12 | $10k to $20k in 5 years is about 14.87% CAGR | $10k to $18k in 3 years is about 21.6% CAGR with a smaller $8,000 gain. Edge case: zero or negative start values break the CAGR exponent, and a mid-course deposit turns a single-path CAGR into an XIRR problem. Both models assume steady rates, so they ignore fees, taxes and drawdowns. The rule of 72 estimates doubling time as 72 ÷ rate, so 8% doubles near nine years, a quick sanity check against the precise formula.
Compound view: Rs 50,000 at 8% over 10 years matures higher with monthly compounding than yearly, with the interest figure growing in step. CAGR view: $10,000 to $20,000 in five years is a 2x multiple, a $10,000 gain and about 14.87% a year. Compare that with $18,000 in three years: a hotter 21.6% but a smaller $8,000 gain. Limitation: these are steady-rate projections, not forecasts, and are informational only, not financial advice. For installment-based returns use the SIP calculator, and to see how prices erode over time use the inflation calculator. Continuous compounding, where the frequency grows without bound, sits just above monthly as the theoretical ceiling, while daily rests already sit close to it in practice.