About TS Tools
TS Tools (tstools.org) is a collection of free online finance calculators designed to make complex money decisions transparent in under three minutes. Whether you are comparing mortgage repayment plans, estimating income tax, or projecting long-term savings, every tool here works instantly — no sign-up, no downloads.
What We Offer
The site currently features 14 English tools (with deep-dive guides), covering:
- Home loans: Mortgage monthly payment, biweekly mortgage payments, equal-principal repayment, prepayment analysis, car loan
- Debt payoff: Credit card payoff planner with minimum vs fixed payment comparison
- Tax & payroll: Personal income tax estimator
- Savings & investing: Compound interest (with and without inflation adjustment), savings goal, budget planner, emergency fund, ROI (return on investment)
Each calculator is paired with a detailed guide explaining the formulas, parameters, and common pitfalls — so you understand the result, not just the number.
Our Principles
1. 100% client-side computation
Every calculator runs entirely inside your browser. The numbers you enter — loan amount, salary, interest rate — are never sent to any server. Close the tab, and the data is gone.
2. Transparent formulas
Every tool documents the formula and assumptions it uses (e.g., the amortized payment formula, tax brackets version), so you can verify results independently.
3. No ads, no accounts, no gimmicks
No login walls, no pop-ups, no dark patterns. Tools should be tools.
Sources & Accuracy
Tax brackets, benchmark rates and policy parameters referenced in our guides are compiled from publicly available official sources and reviewed regularly. Regulations vary by jurisdiction and change over time; results are estimates for reference only — see our Disclaimer for details.
Contact & Feedback
Found a calculation error, an outdated parameter, or want a new tool? Reach us via the Contact page — every message gets read.