Simple interest: P×r×t
Simple interest grows linearly, no compounding. Each year adds same interest: principal × rate × time. Use for short loans and school exercises.
TL;DR
- Interest = Principal × rate × years, rate as decimal
- Formulas: I = P × r × t | A = P + I
- 5k 5% 3y
How it works
Interest = Principal × rate × years, rate as decimal. Total = Principal + Interest. 5k at 5% 3y → 750 interest, 5750 total.
The math
r=5%=0.05. I=5000×0.05×3=750. Linear vs compound: compound would be 5788, slightly higher.
r = percent/100. t in years.
Examples
5k 5% 3y
- Interest 750
- Total 5750
10k 3.5% 7y
- Interest 2450
- Total 12450
When to use it
✦ Loans
Short-term simple loans.
✦ Teaching
Intro to interest.
⚠ Common mistakes
- Using 5 instead of 0.05
- Confusing simple with compound
FAQ (6)
When is simple interest used?
Short loans, school exercises, and some bonds. Most savings use compound.
Simple vs compound?
Simple grows steadily; compound accelerates as interest joins principal.
Are the calculations performed on CalcTracker safe for my privacy?
Yes, all calculations on CalcTracker run exclusively on your local device within the web browser. None of the entered data is sent to external servers or stored remotely. The application is entirely offline-first.
Can I use CalcTracker in offline mode on my smartphone?
Absolutely. CalcTracker is designed as a lightweight, progressive-style web application. Once the page is loaded for the first time, all calculators remain ready to use and fully functional even in the complete absence of an internet connection.
Are the results provided by the calculators accurate for official use?
Our calculators use standard mathematical formulas and verified equations. However, for critical financial, banking, or tax decisions (such as exact car tax or net salary calculations), we always advise consulting with a certified professional or referencing official government portals.
How can I share a specific calculation with someone else?
Simply click the "Share Link" button located in the results panel after performing a calculation. The values entered into the form will be encoded directly into the URL query parameters, allowing anyone who opens the link to see the exact same results instantly.
Sources & References
⚠ Financial Disclaimer
This tool provides estimates for informational purposes only and does not constitute financial, tax, or legal advice. Results may vary based on local regulations, rates, and individual circumstances. Always consult a qualified professional before making financial decisions.