{
  "id": "rd",
  "version": "dea0bc903f9e",
  "status": "published",
  "name": "RD Calculator",
  "question": "What will my RD be worth?",
  "summary": "Computes the maturity value of a recurring deposit: a fixed amount saved every month, with interest compounded every quarter.",
  "category": "finance",
  "subcategory": "investing",
  "url": "https://www.acalculator.org/finance/rd-calculator",
  "markdown": "https://www.acalculator.org/finance/rd-calculator.md",
  "kind": "schedule",
  "method": "Each deposit grows at (1 + r/400) for every quarter it is held, counting part quarters: M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), with i = r/400 and n the number of quarters.",
  "assumptions": [
    "Each deposit is paid at the start of its month, and the last one earns one month of interest.",
    "Interest compounds every quarter, and part quarters earn (1 + r/400)^(months/3), as in the bank formula.",
    "The term is rounded to the nearest whole month.",
    "The rate does not change. Tax (TDS) and early-withdrawal penalties are not included."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "monthlyDeposit": {
        "title": "Deposit each month",
        "description": "The fixed amount paid in at the start of every month.",
        "type": "number",
        "x-unit": "USD",
        "exclusiveMinimum": 0,
        "maximum": 100000000
      },
      "annualInterestRate": {
        "title": "Interest rate (per year)",
        "description": "The yearly interest rate the bank quotes, compounded every quarter.",
        "type": "number",
        "x-unit": "percent",
        "minimum": 0,
        "maximum": 50
      },
      "timePeriodYears": {
        "title": "For how long? (years)",
        "description": "The term of the deposit in years. It is rounded to the nearest whole month.",
        "type": "number",
        "minimum": 0.1,
        "maximum": 50
      }
    }
  },
  "outputs": {
    "maturity": {
      "label": "Maturity value",
      "description": "The balance at the end of the term: every deposit plus all interest.",
      "format": "money"
    },
    "paidIn": {
      "label": "Total deposited",
      "description": "The monthly deposit times the number of months.",
      "format": "money"
    },
    "interest": {
      "label": "Interest earned",
      "description": "The maturity value minus the total deposited.",
      "format": "money"
    },
    "months": {
      "label": "Number of deposits",
      "description": "How many monthly deposits are made.",
      "format": "integer"
    },
    "gain": {
      "label": "Interest as a share of deposits",
      "description": "The interest earned divided by the total deposited, as a percent. It is not a yearly rate.",
      "format": "percent"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "monthlyDeposit": 5000,
      "annualInterestRate": 7.5,
      "timePeriodYears": 1
    },
    "outputs": {
      "maturity": 62478.45917764834,
      "paidIn": 60000,
      "interest": 2478.459177648343,
      "months": 12,
      "gain": 4.130765296080572
    },
    "text": "Depositing $5,000.00 a month at 7.5% in a 1-year deposit gives $62,478.46, of which $2,478.46 is interest."
  },
  "examples": [
    {
      "given": {
        "monthlyDeposit": 5000,
        "annualInterestRate": 7.5,
        "timePeriodYears": 1
      },
      "expect": {
        "maturity": 62478.45917764835,
        "paidIn": 60000,
        "months": 12
      },
      "source": "RD formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)) (ClearTax RD calculator, cleartax.in/s/rd-calculator); hand calculation in content.mdx; Recurring deposit maturity formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), i = r/400, n in quarters: ClearTax RD calculator. https://cleartax.in/s/rd-calculator"
    },
    {
      "given": {
        "monthlyDeposit": 1000,
        "annualInterestRate": 7,
        "timePeriodYears": 5
      },
      "expect": {
        "maturity": 71932.7908836927,
        "interest": 11932.7908836927
      },
      "source": "the same RD formula with i = 0.0175 and n = 20 quarters; hand calculation in content.mdx; Recurring deposit maturity formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), i = r/400, n in quarters: ClearTax RD calculator. https://cleartax.in/s/rd-calculator"
    },
    {
      "given": {
        "monthlyDeposit": 10000,
        "annualInterestRate": 5,
        "timePeriodYears": 0.5
      },
      "expect": {
        "maturity": 60877.43054860966,
        "months": 6
      },
      "source": "sum of 10,000 × (1.0125)^(m/3) for m = 1 to 6; hand calculation in content.mdx; Recurring deposit maturity formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), i = r/400, n in quarters: ClearTax RD calculator. https://cleartax.in/s/rd-calculator"
    },
    {
      "given": {
        "monthlyDeposit": 5000,
        "annualInterestRate": 0,
        "timePeriodYears": 1
      },
      "expect": {
        "maturity": 60000,
        "interest": 0
      },
      "source": "hand calculation in content.mdx: 12 × 5,000 at 0%; Recurring deposit maturity formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), i = r/400, n in quarters: ClearTax RD calculator. https://cleartax.in/s/rd-calculator"
    }
  ],
  "sources": [
    "Recurring deposit maturity formula M = R[(1 + i)^n − 1] ÷ (1 − (1 + i)^(−1/3)), i = r/400, n in quarters: ClearTax RD calculator. https://cleartax.in/s/rd-calculator",
    "Compound interest with part periods: S. A. Broverman, Mathematics of Investment and Credit, chapter 1."
  ],
  "related": [
    "compound-interest"
  ],
  "changelog": [
    {
      "date": "2026-09-29",
      "note": "Worked examples name a published reference for their rule."
    },
    {
      "date": "2026-10-01",
      "note": "The answer sentence reads “a 1-year deposit”, not “for 1 years”."
    }
  ]
}