Interest Calculator

How Interest is Calculated

Simple Interest Formula

SI = (P × R × T) / 100

Where:

• P = Principal amount
• R = Monthly interest rate (₹ per ₹100)
• T = Time in months and days

Compound Interest Formula

A = P × (1 + r/n)nt
CI = A - P

Where:

• A = Final amount
• P = Principal
• r = Annual interest rate (decimal)
• n = Compounding frequency/year (12)
• t = Time in years

Enter your principal, interest rate (per annum or monthly), compounding period (daily, monthly, annually), and duration to see total interest earned, principal plus interest, and growth. Our tools include simple interest calculators, compound interest calculators for different compounding frequencies, and advanced options like reducing interest calculator and savings calculator with compound interest for investments.

Use our interest calculator online to compute simple interest, compound interest, monthly interest, and annual interest for any investment or loan. Whether you need a CD interest calculator, FD interest calculator, RD interest calculator, or want to calculate interest rate for savings accounts, mortgages, credit cards, loans, or security deposits, our calculators work for India, South Africa, Canada, Australia, UK and other countries.

About this Interest Calculator

Interest Calculator India – Simple & Compound Interest with Dates

Use this free interest calculator to calculate interest on any amount using Simple Interest or Compound Interest methods. Just enter the principal, annual interest rate, and select the start and end dates – the calculator accurately computes interest based on full months and remaining days separately.

Switch between monthly compound interest and simple interest calculation modes to compare results. This tool is ideal for:

• Hand loan interest calculation
• Money lending and rural bookkeeping
• Informal loans and personal finance
• Daily, monthly, or yearly interest tracking

Results are shown in the Indian number system (e.g., ₹1,00,000) for easy readability.

Whether you're managing interest between friends, computing village money lending interest, or verifying loan dues, this tool simplifies it all.
Best suited for India-based users needing precise, date-based interest computation.

Learn how to calculate interest, use compound interest formula calculator for compounded returns, find the rate of interest calculator and determine how much interest you’ll earn or pay using accurate, easy online tools trusted by millions (including thecalculatorsite.com, NerdWallet, MoneyChimp, Moneysmart, Tata AIA, HDFC, and more).

Features of the Interest Calculators

• Simple, user-friendly design –Best suited for Indian money lenders,borrowers, and personal finance users
• Supports date format (mm/dd/yyyy) – Ideal for rural interest calculation and desi bookkeeping
• Accurate calculation by full months and remaining days – Useful for hand loan interest and informal lending
• Perfect for rural and informal financial use – Tailored for small-scale money lending and Indian accounting
• Fast loading and fully mobile responsive – Optimized for smartphone users in India
• Clear breakdown of results – Displays principal, simple or compound interest, and total amount in Indian number format (e.g., ₹1,00,000)

• Simple interest calculator online: Find interest with the standard formula Interest = Principal × Rate × Time.
• Compound interest calculator: Calculate growth with compounding frequencies including monthly, quarterly, and annually.
• Monthly interest calculator: Compute monthly interest payments and returns easily.
• Annual interest calculator / Per annum interest calculator: See yearly returns for investments.
• Principal and interest calculator: Total amount including the original principal and interest earned.
• Country-specific calculators: Interest calculator India, South Africa, Canada, Australia, UK with regional rates and products.
• Special calculators: Credit card interest calculator, loan interest calculator, savings interest calculator, RD/FD interest calculator, security deposit interest calculator, GST interest calculator, TDS interest calculator, car interest calculator, mortgage interest calculator, and more.