{"slug":"compound-growth","name":"Compound Growth","category":"fortune","tags":["growing","planning"],"tagline":"What a starting amount plus monthly contributions grows into over time.","endpoint":"https://xearno.tools/api/v1/tools/compound-growth","page":"https://xearno.tools/t/compound-growth","description":"Projects the future value of a lump sum plus recurring monthly contributions at a given annual return, compounded monthly. Splits the outcome into what you put in versus what compounding earned, and sanity-checks the assumptions.","inputSchema":{"type":"object","properties":{"principal":{"description":"Starting amount","type":"number","minimum":0,"default":10000},"monthly":{"description":"Monthly contribution","type":"number","minimum":0,"default":500},"rate":{"description":"Annual return (%) Nominal annual return. 7% is a common long-run equity assumption.","type":"number","minimum":-20,"maximum":50,"default":7},"years":{"description":"Years (yr)","type":"number","minimum":1,"maximum":80,"default":10}},"required":[],"additionalProperties":false},"methodology":["Formula: FV = P·(1+i)^m + C·((1+i)^m − 1)/i, where i is the monthly rate (annual/12) and m the number of months. Contributions are assumed at the end of each month.","The inflation-adjusted figure divides the future value by 1.03^years — a 3% reference, not a forecast. Real (after-inflation) equity returns have historically run around 4–7%.","This is a deterministic projection at a constant rate. Real returns arrive unevenly; the sequence of returns matters for withdrawals but not much for steady accumulation."],"usage":"POST https://xearno.tools/api/v1/tools/compound-growth with a JSON body matching inputSchema."}