Calkura provides free online calculators for finance, health, education and everyday needs — all available without signing up. Whether you're figuring out a mortgage payment, tracking your BMI, or planning for a final exam, our tools give you instant answers with no paywall and no account required.
What we offer
- Financial calculators — compound interest, savings goals, mortgage payoff, loan amortization, credit card payoff, investment returns, rent vs buy, debt payoff strategies, salary conversion, car loans and HELOC analysis.
- Health calculators — BMI with healthy weight ranges and TDEE with calorie targets for weight loss, maintenance or muscle gain.
- Education calculators — weighted grade averages and final exam score planning to help you hit your target grade.
- Everyday tools — exact age calculator with zodiac sign and birthday countdown.
Our methodology
Every calculator uses standard, well-established formulas. Financial tools rely on the amortization formula M = P·r / (1 − (1+r)−n) and month-by-month simulations for scenarios with extra payments or variable periods. The TDEE calculator uses the Mifflin-St Jeor equation, widely considered the most accurate formula for basal metabolic rate. The paycheck calculator uses 2026 IRS progressive tax brackets and FICA rates.
Where a calculation depends on assumptions — such as compounding frequency, activity level, or tax filing status — those assumptions are clearly stated on the page. We cross-check numerical results against closed-form solutions to catch errors.
Privacy first
Every calculation runs entirely in your browser. The numbers you enter are never sent to, stored on, or collected by our servers. We don't use cookies for tracking, and there's no sign-up wall. Your data stays on your device.
Accuracy and disclaimer
Results are estimates for educational and informational purposes only. They are not financial, medical or tax advice. Actual returns, rates, health outcomes and tax obligations vary and are not guaranteed. For important decisions, consult a qualified professional.
Contact
Questions, corrections, or suggestions? Email us at hello@calkura.com.