Free calculators for money, study, health and everyday life
39 quick, private tools that run entirely in your browser. No sign-up, and nothing you type is stored.
- 100% free
- No account needed
- Private - runs on your device
All calculators
- Loan CalculatorMonthly payment, total interest and amortization
- Mortgage CalculatorFull monthly payment with tax, insurance and PMI
- Auto Loan CalculatorCar payment with sales tax, fees and trade-in
- Compound InterestHow savings grow with regular contributions
- Savings Goal CalculatorHow much to save each month to reach a goal
- Retirement SavingsWhat your pot could be worth when you retire
- ROI CalculatorReturn on an investment, total and per year
- ROI ComparisonCompare returns on several investments side by side
- Credit Card PayoffHow long until you're debt-free, and the interest
- Debt Payoff PlannerCompare the avalanche and snowball methods
- Inflation ImpactWhat your money will really be worth later
- Salary to HourlyConvert between hourly, monthly and annual pay
- GPA CalculatorWeighted and unweighted GPA on a 4.0 scale
- Final Grade PredictorThe score you need on your final exam
- Weighted Grade CalculatorCourse grade from weighted scores
- Percentage / Grade ConverterConvert between percentages and letter grades
- Study Time PlannerSplit your weekly study hours by priority
- Fraction CalculatorAdd, subtract, multiply and divide fractions
- Statistics CalculatorMean, median, mode and standard deviation
- Base64 Encoder/DecoderEncode or decode text, with full Unicode support
- URL Encoder / DecoderPercent-encode or decode URLs
- JSON FormatterValidate, format or minify JSON
- Password GeneratorStrong random passwords and a strength checker
- UUID GeneratorRandom version 4 UUIDs, in bulk
- Hash GeneratorSHA-256, SHA-1 and SHA-512 of text or files
- Time Zone ConverterConvert a time between any two time zones
- Unix Timestamp ConverterEpoch time to date, and back
- Word & Character CounterWords, characters, sentences and reading time
- Color ConverterHEX, RGB and HSL, with a WCAG contrast check
- Tip CalculatorWork out the tip and split the bill
- Percentage CalculatorPercent of a number, ratios and percent change
- Unit ConverterLength, weight, volume and temperature
- Age CalculatorExact age and days until your next birthday
- Date CalculatorDays between dates, or add and subtract time
- Fuel Cost CalculatorWhat a trip costs in fuel, in mpg or L/100 km
Frequently asked questions
Are these calculators really free?
Yes! All calculators on Smart Calculator Hub are 100% free with no registration, subscriptions, or hidden costs.
Do I need to create an account?
No account needed. Simply choose a calculator and start calculating immediately.
How accurate are the calculations?
Our calculators use standard, widely published formulas. Results are estimates, so please verify important figures with a professional.
Can I use these calculators on mobile?
Absolutely! All calculators are fully responsive and work perfectly on smartphones, tablets, and desktop computers.