How we calculate · Savings goal

How the savings goal calculator works

Clear growth math for learning—not bank quotes or advice.

John Rey Balais, developer of Nestfigure Written & maintained by John Rey Balais Developer · Nestfigure

Tool: Savings goal calculator · Embed · All how-we-calculate pages · Questions

Purpose

Estimate how many months of deposits (and optional APY growth) may take to reach a target balance under stated assumptions. Educational only.

Core model

  • Monthly rate from APY: m = (1 + APY)^(1/12) − 1 when APY > 0; otherwise 0
  • Each month: interest = starting balance × m
  • Then add the monthly deposit
  • Repeat until balance ≥ goal or a safety cap (600 months)

What we intentionally leave out

  • Fees, taxes on interest, and early-withdrawal rules
  • Live bank APYs or product recommendations
  • Irregular deposit schedules and one-time bonuses (except starting balance)
  • Investment market risk (this is a steady APY-style model only)

Related

Last reviewed: August 9, 2026.

YMYL notice: This site is for education only. It is not financial, tax, or investment advice. Nestfigure is not a bank, credit union, broker, investment adviser, or fiduciary. Product terms, rates, and penalties vary—always read your institution’s disclosures before acting. Calculator results are mathematical estimates, not bank quotes.