Compound Interest Calculator

Model growth, withdrawal, and goal compound interest scenarios. Fully offline.

Plan long-term savings with a compound interest calculator that shows the numbers behind every scenario. Enter initial investment, monthly contribution, annual rate, and horizon to see future value, total contributions, and total interest year by year.

All math runs on-device. No signup or sync, and nothing leaves your phone.

**Growth:** Project how savings build up over 20 or 30 years with monthly additions. Daily, monthly, quarterly, semi-annual, and annual compounding supported, with contributions timed at period start or end.

**Withdrawal:** See how long retirement savings last at a given monthly drawdown. Factor in expected return and inflation to find the depletion year. Tailored for FIRE and post-retirement planning.

**Goal:** Set a target amount and back-solve the monthly contribution needed, or the years required at a fixed contribution. Numerical bisection gives fractional-year precision.

The compound interest engine drives all three modes with identical accuracy. Every projection comes with a year-by-year table that expands to monthly detail. Three chart variants (trend, yearly bars, composition donut) are switchable from the result screen. Export as PDF or share as image. Saved scenarios reload any time.

Four languages (English, Korean, Chinese, Japanese) and a currency picker covering $, ₩, ¥, €, £, and more. Light, dark, and system themes.

A compound interest calculator is most useful when the numbers match your actual plan. Results are for reference only and do not constitute investment advice.