Deposit Calculator - Fixed Deposit Maturity | Financial Calculator

Free fixed deposit calculator to estimate maturity amount after tax. Calculate pre-tax interest, tax deduction, and final payout for term deposits.

Fixed deposits in this model

A fixed (term) deposit is a single lump sum left untouched at an agreed rate until maturity. The calculator defaults to simple interest because most term deposits credit interest once, at maturity, rather than compounding it. It then applies the interest income tax on earnings and reports the after-tax payout — the figure that actually lands in an account when the term ends.

Worked example at a hypothetical rate

Placing $25,000 at a 4% annual rate for 18 months: simple interest = $25,000 × 4% × 1.5 years = $1,500.00. The 15% tax deducts $225.00, leaving an after-tax maturity amount of $26,275.00. Switching to monthly compounding for the same inputs would lift pre-tax interest slightly above the simple-interest figure. All rates are illustrative and informational only.

How to Use

  1. Deposit Amount — Enter the lump sum you plan to lock in, for example $10,000
  2. Annual Interest Rate — Enter the annual rate (%) quoted for the fixed-deposit product
  3. Deposit Period — Enter the term in years or months — common terms run from 6 months to 3 years
  4. Interest Type — Keep simple interest (typical for term deposits) or switch to compounding with annual, semi-annual, quarterly, or monthly frequency
  5. Calculate — Click Calculate to see pre-tax interest, the tax deduction, and the after-tax maturity payout
  6. Use Rate Presets — Tap the preset rate buttons to compare typical rate levels side by side without retyping

FAQ

What is the difference between a fixed deposit and a savings account?

A fixed deposit locks in a lump sum at a fixed rate using simple interest. A savings account accepts regular monthly contributions. Fixed deposits are ideal for lump sum investment.

Are there ways to reduce income tax on deposits?

Yes — tax-advantaged accounts can reduce or eliminate interest income tax. Check with your bank or financial institution for available options.

How much deposit insurance coverage is there?

Coverage varies by country. In Korea, deposits are protected up to ₩50 million per institution. Amounts above this limit should be spread across multiple banks for safety.

How is simple interest on a term deposit computed?

Interest = principal × annual rate × (months ÷ 12). A $10,000 deposit at a hypothetical 3.5% for 12 months earns $350.00 pre-tax; after the English edition's 15% interest tax ($52.50) the maturity payout is $10,297.50.

What changes when I pick compound interest?

The calculator switches to A = P(1 + r/n)^(nt) with your chosen frequency (1, 2, 4, or 12 periods per year), so credited interest itself earns interest. Over a 1-year term the gap versus simple interest is small, but it widens as the term grows.

Which tax rate is applied to the interest?

Each language edition applies a typical local interest tax — 15% in the English edition. The deduction applies to interest only, never to your principal, and tax-advantaged accounts may reduce it further.