Welcome to umrechner.online!
Glad you're here! We are your go-to resource for precise online calculations and unit conversions. Whether you need to quickly convert kilometres to miles, calculate your BMI, or perform professional colour conversions — you'll find the right tool here.
What Makes umrechner.online Special?
Over 79 Free Calculators & Converters
From length conversion to weight calculators to specialist tools like the hyperfocal distance calculator for photographers or pipe sizing for engineers — we cover almost every need.
- Unit conversions: Length, weight, area, volume, temperature, time, speed, pressure, power, and more
- Practical calculators: Percentage, rule of three, gross/net, fuel cost, ideal weight, CO2 footprint
- Specialist tools: Colour converter (RGB/CMYK/Pantone), wallpaper calculator, cooking times, portion scaling
- Professional tools: Electrical power, voltage drop, cable sizing
Available in 5 Languages
Our calculators speak your language: German, English, French, Spanish, and Polish. Perfect for international teams or when you're travelling abroad.
100% Free — Forever
No hidden costs, no registration, no premium features. All 79 calculators are completely free and unrestricted. That has always been our philosophy and will remain so.
Works Everywhere
At your desktop in the office, on a tablet at home, or on your smartphone on the go — our calculators are fully responsive and work flawlessly on all devices.
Maximum Precision
All conversions are based on official conversion factors and deliver professionally accurate results. Rely on mathematical correctness for study, work, and everyday life.
Who Is umrechner.online For?
Anyone who wants to save time! Our users are diverse:
- Students — for physics, chemistry, mathematics, and engineering
- Home cooks — converting US recipes with cups and ounces
- Athletes — distances, speeds, calorie burn
- Tradespeople — areas, material quantities, cable cross-sections
- Designers — colour conversion, pixel calculations, DPI conversion
- Travellers — distances, temperature, time zones
- Business professionals — percentages, discounts, gross/net, rule of three
How Does It Work?
Simple — just three steps:
- Choose a calculator — use the search or browse the categories
- Enter your values — type in your numbers and select the units
- Get your result — instant real-time calculation
No registration, no download, no app — just open your browser and get started!
New: Tutorials for Every Calculator!
Not sure how a calculator works? No problem! We have created a detailed tutorial for each of our 79 calculators, with step-by-step instructions and examples that anyone can follow — no technical background required.
Popular Calculators to Get Started
- Percentage Calculator — the classic for discounts, interest, and increases
- Weight Converter — kg, grams, pounds, ounces, and more
- Length Converter — metres, kilometres, miles, inches
- Gross-Net Calculator — salary calculator for Germany
- Fuel Cost Calculator — petrol costs for your trip
- Colour Converter — RGB, CMYK, HEX, Pantone, HKS, RAL
Our Promise to You
Always free — no hidden fees, ever
Privacy — no unnecessary cookies, no excessive tracking
Continuous improvement — new calculators based on your requests
Support — contact us with questions or feature requests
