ST Calculator is a suite of free financial calculators designed for clarity: transparent formulas, full breakdowns, and practical, transparent results.
What we build
Each tool answers a practical money question — growth, payments, inflation, savings targets — with the same layout: inputs, results, charts, and the math behind the numbers.
How calculations work
- All math runs in your browser using standard formulas (compound interest, amortization, inflation adjustment, goal-seeking contributions).
- Formulas are shown on each page so results are not a black box.
- Each tool is a self-contained page focused on a single problem.
Privacy
Scenario inputs can be saved in your browser’s local storage if you use “Save scenario.” That data does not leave your device through ST Calculator. We do not require accounts for core calculators.
Not financial advice
ST Calculator is an educational planning toolkit. Results depend on the assumptions you enter (rates, terms, inflation). They are not personalized advice, credit offers, or guarantees of future returns.
Accuracy
We aim for correct implementation of well-known formulas. Rounding, compounding conventions, and fees in real products may differ. Always verify critical decisions with a qualified professional or your lender/institution.
Contact
For methodology questions or corrections: hello@stcalculator.com (replace with your real address when the domain is live).
Last updated: 31 August 2026 · English language site