Free Online Calculators

Finance, health, date, and math calculators.

Fast, accurate calculators for everyday math, finance, health, and time. Each calculator shows its formula so you can verify and learn.

Problems calculators solve

  • Calculating sale prices and the exact discount percentage during shopping
  • Figuring out your precise age in years, months, and days for paperwork
  • Adding or subtracting VAT/GST for invoices and receipts
  • Computing profit margins and markups for product pricing
  • Checking BMI and healthy weight range estimates
  • Solving percentage-of and percentage-change problems quickly

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Who uses calculators?

  • Shoppers checking real discount amounts
  • Freelancers and small business owners pricing work
  • Students handling math homework and conversions
  • Accountants preparing quick invoice numbers
  • Health-conscious users tracking BMI and metrics
  • Event planners calculating ages and date differences

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Tutorials and guides about calculators.

Frequently asked questions

The math is accurate to double-precision floating point, but calculators like loan or VAT should be used as a guide — consult a professional for official figures, especially where legal or regulatory rules apply in your country.
Yes — you can enter any VAT or GST rate. Common presets for the UK, EU, Australia, and Canada are included, but you can override the rate manually for anywhere else.
The age calculator accounts for leap years, month lengths, and time-zone differences in the birth date. Results are correct to the day, including for people born on February 29.
BMI is a rough screening tool, not a diagnosis. It doesn't account for muscle mass, body composition, age, or ethnicity, so athletes and elderly users especially should treat the number as one data point among many. Consult a clinician for a real health assessment.
Yes. Enter your cost (materials + hours × rate) and target selling price to see margin and markup. It works for physical products and service-based businesses alike.
For convenience, some calculators remember your last inputs in local storage so you don't have to re-enter them. Nothing is sent to a server — you can clear local storage any time to wipe the history.

Your files never leave your device

Every tool on Xevon Tools runs 100% in your browser. No uploads, no servers, no tracking. Free forever.

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