Savings, Budget & Compound Interest Calculator
Give every pound a purpose. Plan your spending, find room to save, and see what time and compound interest could do.
01Your income
Enter take-home income after tax. Each line can use its own payment frequency.
02Spending & savings
Keep savings allocations separate from spending by choosing the Savings category. Weekly entries use 52 weeks ÷ 12 months.
Your plan, on your terms
A JSON backup includes both tools. You control the file and where you keep it. Clearing removes this app’s saved draft from this browser.
Your income, spending and planned savings in one place.
Your savings capacity
Copies income minus spending to the compound calculator. This includes existing savings allocations; it does not add them twice.
Where your money goes
Monthly equivalentMonthly & annual outlook
The annual outlook repeats this budget for 12 months. It assumes income and costs stay constant and does not include savings interest.
Budget entries
Contributions plus compound interest.
What does “today’s money” mean?
Inflation changes how much money can buy. This figure adjusts your projected future balance for the annual inflation rate you entered, so you can compare its buying power with prices today.
For example, 10,000 in 10 years would buy about what 7,441 buys today if inflation averages 3% a year.
Your savings balance is not reduced by this adjustment. It is a different way of viewing the same future money. With 0% inflation, both figures are the same. This is an illustration, not a forecast.
Watch your savings grow
Your savings, period by period
How the planner works
Your information stays in this browser. Autosave uses local storage on this device. This app sends no income, expenses or savings figures to a server and makes no external requests. Download a JSON backup before changing browser or device; clearing browser storage also clears an autosaved plan.
- Budget conversions use 52 weeks, 26 fortnights and 12 months per year. Amounts are entered in the selected currency; changing currency changes the symbol only and does not convert exchange rates.
- AER is the effective return over a year. For a nominal rate, the annual growth factor is (1 + annual rate ÷ compounding periods)periods. Between contribution dates the model uses the equivalent fractional-period growth, so all payment frequencies can be compared consistently.
- Weekly and fortnightly contributions are evenly spaced over a 52-week year. Only payments scheduled within the selected duration are included. Beginning-of-period contributions start immediately; end-of-period contributions start after one period.
- Annual contribution increases apply after each full saving year. Projected interest is not rounded at every posting; banks may calculate daily, round differently or change their rates.
- Figures exclude tax, fees, withdrawals and investment volatility. Rates and inflation remain constant. These are planning illustrations and are not guaranteed returns.
- Goal estimates look up to 100 years ahead at your current settings. A quoted goal date is a duration from the start of this plan, not a calendar-date promise.
Reda Apps · Savings, Budget & Compound Interest Calculator v1.0.2 · Private calculations · Illustrations exclude tax and fees.