Deposit Interest Calculator
Estimate the gross interest, withholding tax, net return, and total payout for a fixed-term bank deposit. This calculator is useful for quick comparisons between rates, currencies, and maturity dates.
Calculator
Uses simple interest: principal × annual rate × days / day-count basis.
Your estimated return
General estimate only. Bank rounding rules, product terms, and tax treatment may vary.
How this deposit interest calculator works
The calculator uses a simple-interest method, which is common for fixed-term deposits. It counts the exact number of calendar days between the start date and maturity date, then applies the annual interest rate proportionally.
The result separates gross interest from tax withheld, so you can quickly see the net amount you may receive at maturity. This is useful when comparing different deposit offers or checking whether a higher rate still gives a better net return after tax.
Deposit interest formula
Gross interest = principal × annual rate × days / day-count basis
Net interest = gross interest − withholding tax
For example, a 10,000 RON deposit at 4.5% for 91 days on Actual/365 produces about 112.19 RON gross interest. With 10% tax, the estimated net interest is about 100.97 RON.
Actual/365 vs Actual/360
The day-count basis affects the final interest amount. Actual/365 divides the yearly rate by 365 days and is common for many retail deposits. Actual/360 divides the yearly rate by 360 days and is used in some banking or money-market contexts.
If you are comparing offers, use the convention shown in the bank contract. If it is not listed, ask the bank before relying on the final payout estimate.
Important notes before using the result
This tool is for informational use only and does not replace financial advice. It does not account for early withdrawal penalties, promotional conditions, compounding, deposit insurance limits, currency conversion fees, or special tax situations.
FAQ
What is the difference between gross and net interest?
Gross interest is the amount earned before tax. Net interest is what remains after the selected withholding tax is deducted.
Does this calculator work for EUR or USD deposits?
Yes. Select the currency and enter the deposit amount, rate, and dates. The formula works the same, but tax and bank rules may differ.
Should I use Actual/365 or Actual/360?
Use the convention from your deposit agreement. For many retail deposits Actual/365 is common, but some products use Actual/360.
Does this include compound interest?
No. This version estimates simple interest. If your deposit capitalizes interest monthly or yearly, the final return may differ.