Online calculators
JustCalcs is a catalogue of clear calculators for everyday questions. Every tool is free, works on a phone and shows the formula behind the answer, not just the number.
Results are shareable: the values you enter are stored in the page address.
- Time Unit Convertertime converterOpen →
- Temperature Convertertemperature converterOpen →
- Length Converterlength converterOpen →
- Weight Converterweight converterOpen →
- Scale Calculatorscale calculatorOpen →
- Data Storage Converterdata storage converterOpen →
- Area Converterarea converterOpen →
- Power Converterpower converterOpen →
- Speed Converterspeed converterOpen →
- Pressure Converterpressure converterOpen →
- Volume Convertervolume converterOpen →
How the catalogue is organised
Calculators are grouped into sections: unit converters, date and time, fitness, travel, home improvement, money and cooking. Pages inside a section link to each other, so moving from one calculation to a related one takes a single click.
What makes these calculators different
- The formula and a worked example sit next to the result, so the number is verifiable.
- Exact conversion factors with no rounding in intermediate steps.
- Built for mobile: large fields, readable tables, nothing cut off.
- No accounts, no interstitials, no required subscriptions.
What comes next
The catalogue grows section by section: date calculations, more unit converters and everyday money tools are next. Published pages are updated whenever a formula changes or a new calculation mode is added.
Frequently asked questions
Are the calculators free?
Yes, every calculation is free and requires no account.
Do they work on a phone?
Yes. The layout is built for small screens: fields and tables adapt to the width.
How do I share a result?
Your input is stored in the page address. Use the button under the calculator to copy the link with the calculation.
How reliable are the results?
Each page states the formula and the factors used, so you can check them. For legal, tax and medical decisions, confirm against official sources.