Everyday Calculators guide 2026
Date, business day, mortgage, tax, BMI, unit, fuel, shipping, and e-commerce calculations. Every listed task has its own URL, immediate workspace, examples, explanations, FAQs, and related links.
All 10 tools in this category
- Age and Birthday Calculator：Enter a birth date and target date to calculate exact years, months, days, total months, weeks, days, and next birthday.
- Date Difference Calculator：Calculate days, weeks, calendar months, hours, and minutes between two dates, including weekday and weekend counts.
- Workday Calculator：Add or subtract business days with configurable weekend rules and a custom holiday list.
- Mortgage and Interest Calculator：Compare equal-payment and equal-principal loans with monthly payment, total interest, and a full amortization schedule.
- China Income Tax Estimator：Estimate accumulated individual income tax, average monthly tax, and take-home pay under China resident comprehensive-income brackets.
- BMI and Calorie Calculator：Calculate BMI, basal metabolic rate, maintenance calories, and healthy weight range from body measurements and activity.
- Unit Converter：Convert accurately between length, mass, area, volume, temperature, speed, and digital storage units.
- Fuel Consumption Calculator：Calculate L/100km, km/L, US MPG, trip fuel cost, and cost per distance from mileage and fuel used.
- Volumetric Weight Calculator：Calculate dimensional and billable weight from package dimensions, divisor, actual weight, and quantity.
- E-commerce Profit Calculator：Combine price, product cost, shipping, platform fee, advertising, refunds, tax, and other costs to estimate net profit.
How to choose a workflow
Start with the page that describes the exact input and result you need. Deterministic conversion and calculation run locally, while OCR or dictionary workflows may download a browser runtime on first use.
Privacy, mobile use, and result checks
No account is required for the basic workflow. Files and text remain in the current browser. On a phone, smaller files are recommended. Always verify dates, amounts, names, units, recognized text, and downloaded output before formal use.
Frequently asked questions
Can I use every basic function without signing in?
Yes. Open the specific page and start immediately.
Are uploaded files stored by the site?
No. These workflows process the source in the browser and do not send it to the site server.
Why can the first OCR or dictionary run take longer?
The browser downloads the required runtime or language data once before processing.