Simple Interest Calculator - SI Formula Calculator Online
Calculate simple interest instantly using the SI formula (P × R × T) / 100. Free online calculator for loans, fixed deposits, savings with monthly & daily interest breakdown.
Simple Interest Calculator Tool
₹ 1,00,000
Live Calculation
SI = (1,00,000 × 10 × 5) / 100
= ₹ 50,000
Total Interest
₹50.00 K
Monthly Interest
₹833.33
Daily Interest
₹27.40
Principal vs Interest Breakdown
Simple Interest grows linearly. For exponential wealth growth, try SIP investment instead!
Simple Interest Calculator Examples
Quick reference for common loan & deposit scenarios at 8% per annum
| Principal | 1 Year SI | 3 Years SI | 5 Years SI | 10 Years SI | Total (10 Yrs) |
|---|---|---|---|---|---|
| ₹10,000 | ₹800 | ₹2,400 | ₹4,000 | ₹8,000 | ₹18,000 |
| ₹50,000 | ₹4,000 | ₹12,000 | ₹20,000 | ₹40,000 | ₹90,000 |
| ₹1,00,000 | ₹8,000 | ₹24,000 | ₹40,000 | ₹80,000 | ₹1.80 L |
| ₹5,00,000 | ₹40,000 | ₹1.20 L | ₹2 L | ₹4 L | ₹9 L |
| ₹10,00,000 | ₹80,000 | ₹2.40 L | ₹4 L | ₹8 L | ₹18 L |
*All calculations at 8% per annum simple interest rate.
What is Simple Interest?
Simple Interest (SI) is a quick and straightforward method of calculating the interest charge on a loan or earned on a deposit. The interest is calculated only on the original principal amount and doesn't compound over time.
Unlike compound interest where interest earns interest, simple interest provides linear growth. This makes it ideal for short-term loans, certain bonds, and basic financial calculations.
हिंदी में: साधारण ब्याज (Simple Interest) सिर्फ मूल राशि पर लगाया जाता है। समय बढ़ने पर भी ब्याज की राशि हर साल समान रहती है। यह छोटी अवधि के लोन और बेसिक हिसाब के लिए सबसे अच्छा है।
Simple Interest Formula
SI = (P × R × T) / 100
- • SI = Simple Interest
- • P = Principal Amount
- • R = Rate of Interest per annum (%)
- • T = Time period in years
Total Amount = Principal + Simple Interest
A = P + SI = P(1 + RT/100)
Where is SI Used?
Car Loans
Most auto loans use simple interest method
Personal Loans (Short-term)
Quick personal loans often use SI
Treasury Bills
Government short-term securities
Certificate of Deposits
Some CDs use simple interest
Inter-personal Lending
Money lent between individuals
Educational Examples
Most school-level math problems
Solved Example
Problem: Calculate simple interest on ₹50,000 at 10% per annum for 5 years.
Given: P = ₹50,000, R = 10%, T = 5 years
SI = (P × R × T) / 100
SI = (50,000 × 10 × 5) / 100
SI = 25,00,000 / 100
SI = ₹25,000
Total Amount = 50,000 + 25,000 = ₹75,000
Simple Interest vs Compound Interest
| Parameter | Simple Interest | Compound Interest |
|---|---|---|
| Calculation Base | Only on principal | Principal + accumulated interest |
| Formula | SI = (P×R×T)/100 | A = P(1+r/n)^(nt) |
| Growth Pattern | Linear (constant) | Exponential (faster) |
| Returns on ₹1L @10% for 10 yrs | ₹1,00,000 | ₹1,59,374 |
| Best For Borrowers | Yes (less to pay) | No (more to pay) |
| Best For Investors | No (less returns) | Yes (more returns) |
| Used In | Car loans, T-bills | FDs, mutual funds, savings |
| Complexity | Very Simple | Moderate |
Frequently Asked Questions
Everything about Simple Interest calculations
What is simple interest?▼
What is the formula for simple interest?▼
How do you calculate simple interest with example?▼
How to calculate simple interest for months?▼
How to calculate simple interest for days?▼
What is the difference between simple and compound interest?▼
Which is better - simple or compound interest?▼
Where is simple interest used in India?▼
Do banks use simple or compound interest?▼
How to find principal from simple interest?▼
How to find rate of interest in simple interest?▼
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Important Disclaimer
"The Simple Interest Calculator provides calculations for educational and informational purposes only. For actual loan or investment decisions, please verify with your bank or financial institution as actual interest calculations may include additional charges, processing fees, or different compounding methods. Consult a financial advisor for personalized advice. Content by Rahul Kumar for SmartFintool."