Savings goal calculator

How it works

What you already have grows at the monthly rate for the number of months you entered, using FV = C × (1 + i)^N where i is the annual rate divided by 100 and then by 12 and N is the number of months. The gap left is the target minus that figure. The monthly deposit needed to close the gap is PMT = gap × i ÷ ((1 + i)^N − 1), the standard annuity formula for payments made at the end of each month. At a 0% rate it simplifies to the gap divided by the number of months. The assumptions are stated because they matter: one fixed rate for the whole period, interest added every month, no withdrawals, and a deposit at the end of every month without fail. Results are an estimate from those assumptions, not financial advice.

Worked example

A goal of 10,000 with 2,000 already saved, 4% a year over 5 years: i = 0.04 ÷ 12 = 0.003333 and N = 60. The 2,000 grows to 2,000 × 1.003333^60 = 2,441.99, leaving 10,000 − 2,441.99 = 7,558.01 to find. The monthly deposit is 7,558.01 × 0.003333 ÷ (1.003333^60 − 1) = 114.00. With no interest the same goal would need (10,000 − 2,000) ÷ 60 = 133.33 a month.

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