Data sources
All country-specific rules (tax slabs, EPF rates, GST rates, etc.) come from official government sources:
- India: Income Tax Department, EPFO, IRDAI, RBI, MOSPI
- US: IRS, Social Security Administration, Federal Reserve
- UK: HMRC, ONS
- Canada: CRA, Statistics Canada
- Australia: ATO, ASIC
Each data file records sourcename, sourceurl, and last_verified date. A warning banner appears when data is older than 18 months.
Formula accuracy
Calculators use standard financial mathematics:
- EMI: Standard annuity formula: P × r × (1+r)^n / ((1+r)^n - 1)
- Compound interest: A = P(1 + r/n)^(nt)
- IRR: Newton-Raphson iteration (200 iterations)
- NPV: Standard discounted cash flow
- Tax: Progressive slab computation with applicable surcharges and cess
All calculations are performed client-side in your browser — no data is sent to our servers.
What calculators cannot do
- Predict market returns
- Account for individual circumstances not covered by inputs
- Replace personalised financial advice from a qualified professional
These calculators are educational tools. They give you a framework for thinking about money decisions, not a final answer. For significant financial decisions (home purchase, retirement planning, tax filing), consult a qualified financial advisor.
Reporting errors
Found a calculation error or outdated data? Email trilumos.app@gmail.com with the calculator name and the error.