Free online calculators
Calculate costs, installments and metrics in one place. Set currency and units (default: US — USD, miles, gallons, lb) in the page header — all calculators use them.
See all online calculatorsAbout Calcboxer
Calcboxer offers hundreds of free online calculators: finance and taxes, health, motoring, math, construction, ecology, and tools for AI regulation and compliance (GDPR, model risk, documentation). Everything runs in your browser with no account required.
You set currency and units (metric or US customary) in the page header; those choices stay consistent across calculators. The site is available in English and Polish. Use the contact page for questions; social profiles are linked in the footer.
Popular calculators
Most used free online calculators — no signup:
Calculator categories
Why us
- No login — use any calculator immediately
- Any device — works on desktop, tablet and phone
- Clear results — breakdown and monthly cost
Frequently asked questions
- Are Calcboxer calculators free?
- Yes. All calculators on the site are free and require no registration. You can use them on desktop, tablet and phone.
- What calculator categories are available?
- We offer calculators for: finance (VAT, loan, instalment, savings), health (BMI, BMR), motoring (fuel consumption, TCO, fuel cost), payroll (gross-net), mathematics (percentages), date and time, unit converters and more.
- Are the calculator results reliable?
- We use widely recognised formulas (e.g. Mifflin-St Jeor for BMR, standard VAT formulas). Results are for guidance only; for tax or medical matters we recommend consulting a professional. More sources are listed in the Sources section below.
- Can I use the site in English?
- Yes. You can switch the language to EN in the top-right corner. Polish and English versions are available.
Calculator categories — overview
| Category | Example calculators |
|---|---|
| Finance | VAT, loan instalment, savings, APR, interest |
| Health | BMI, BMR, TDEE, calorie needs |
| Motoring | Fuel consumption, fuel cost, TCO, travel time |
| Salary and work | Gross-net, leave, hourly rate |
| Mathematics | Percent of number, percentage change, rule of three |
| AI regulation | AI risk index, DPIA, GDPR fine, risk matrix, LLM. |
Sources and definitions: Wikipedia — kalkulator, gov.pl — finanse Wikipedia — calculator, USA.gov — money. Page updated in 2026.