Free Online Tools & Converters
Professional unit converters for temperature, length, weight, currency, volume, speed, area, time, digital storage, and pressure. Convert units instantly with real-time calculations, favorites, and history.
🔥 Most Popular Unit Conversions
Quick access to the most searched conversions. Click any link for instant results:
📊 Quick Conversion Reference Tables
Quick reference tables for common unit conversions. Use these tables for instant conversions or click through to our detailed converters for precise calculations.
Temperature Conversion Table
| Celsius | Fahrenheit | Kelvin | Common Use |
|---|---|---|---|
| -40°C | -40°F | 233 K | Extreme cold |
| 0°C | 32°F | 273 K | Freezing point |
| 20°C | 68°F | 293 K | Room temperature |
| 37°C | 98.6°F | 310 K | Body temperature |
| 100°C | 212°F | 373 K | Boiling point |
Length Conversion Table
| Centimeters | Inches | Feet | Meters |
|---|---|---|---|
| 2.54 cm | 1 inch | 0.083 ft | 0.025 m |
| 30.48 cm | 12 inches | 1 foot | 0.305 m |
| 100 cm | 39.37 inches | 3.28 ft | 1 meter |
| 160 cm | 5'3" | 5.25 ft | 1.60 m |
| 180 cm | 5'11" | 5.91 ft | 1.80 m |
Weight Conversion Table
| Kilograms | Pounds | Ounces | Common Use |
|---|---|---|---|
| 1 kg | 2.20 lbs | 35.27 oz | Food ingredient |
| 50 kg | 110 lbs | - | Average weight |
| 70 kg | 154 lbs | - | Adult weight |
| 100 kg | 220 lbs | - | Heavy weight |
🛠️ All Unit Converters
Choose from our professional unit converters. Each converter supports real-time calculations, favorites, and history:
Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin. Perfect for weather, cooking, and scientific calculations.
Length Converter
Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles.
Weight Converter
Convert between milligrams, grams, kilograms, pounds, ounces, and stones. Ideal for cooking and body weight.
Currency Converter
Convert between 150+ world currencies with live exchange rates. Updated hourly for accurate conversions.
Volume Converter
Convert between milliliters, liters, gallons, cups, tablespoons, and more. Perfect for cooking and liquid measurements.
Speed Converter
Convert between km/h, mph, knots, m/s, and Mach. Useful for vehicle speed, wind speed, and aviation.
Area Converter
Convert between square meters, square feet, acres, hectares, and more. Ideal for real estate and land measurements.
Time Converter
Convert between milliseconds, seconds, minutes, hours, days, weeks, months, and years.
Digital Storage Converter
Convert between bits, bytes, KB, MB, GB, TB, and PB. Supports both binary (1024) and decimal (1000) standards.
Pressure Converter
Convert between Pascal, PSI, bar, atmosphere, Torr, and mmHg. Useful for tire pressure and weather.
Why Use Our Unit Converters?
Real-Time Conversion
Instant results as you type
Mobile-Friendly
Works perfectly on all devices
Favorites & History
Save your common conversions
Live Currency Rates
Updated hourly exchange rates
Privacy-Focused
No data collection, completely free
150+ Units
Support for all major unit types
🎓 How to Use Our Unit Converter
- Step 1: Choose Your Conversion Category - Select from 10 categories: Temperature, Length, Weight, Currency, Volume, Speed, Area, Time, Digital Storage, or Pressure.
- Step 2: Select Source Unit - Choose the unit you want to convert FROM using the dropdown menu.
- Step 3: Enter Value - Type the number you want to convert in the input field. You can use whole numbers or decimals.
- Step 4: Select Target Unit - Choose the unit you want to convert TO from the second dropdown.
- Step 5: View Instant Result - The converted value appears immediately in real-time as you type. No "Calculate" button needed!
Pro Tips:
- Use Quick Links: Click popular conversions above for instant results
- Bookmark Favorites: Save your frequently used conversions
- Mobile-Friendly: Works perfectly on smartphones and tablets
- Copy Results: Click to copy converted values to clipboard
- History: Access your recent conversions anytime
📚 Complete Unit Conversion Guide
Temperature Conversions Explained
Temperature is measured in three main scales: Celsius (°C), Fahrenheit (°F), and Kelvin (K).
Celsius (°C):
Used globally for everyday temperature. Water freezes at 0°C, boils at 100°C. Standard in science and most countries.
Fahrenheit (°F):
Used primarily in the United States. Water freezes at 32°F, boils at 212°F. Common in daily weather forecasts (US).
Kelvin (K):
Used in scientific calculations. Absolute zero at 0 K (-273.15°C). No negative temperatures.
Common Temperature Reference Points:
- -40°C = -40°F (only point where they match)
- 0°C = 32°F (freezing point of water)
- 25°C = 77°F (comfortable room temperature)
- 37°C = 98.6°F (normal body temperature)
- 100°C = 212°F (boiling point of water)
Length & Distance Conversions Explained
Length can be measured in metric (meters, centimeters) or imperial (feet, inches) units.
Metric System:
- Millimeter (mm) - 1/1000 of a meter
- Centimeter (cm) - 1/100 of a meter
- Meter (m) - Base unit
- Kilometer (km) - 1000 meters
Imperial System:
- Inch (in) - 1/12 of a foot
- Foot (ft) - Base unit for short distances
- Yard (yd) - 3 feet
- Mile (mi) - 5,280 feet
Key Conversion Factors:
- 1 inch = 2.54 cm (exact)
- 1 foot = 30.48 cm
- 1 meter = 3.281 feet
- 1 mile = 1.609 km
- 1 km = 0.621 miles
Weight & Mass Conversions Explained
Weight is measured in metric (grams, kilograms) or imperial (pounds, ounces) units.
Metric System:
- Milligram (mg) - 1/1000 of a gram
- Gram (g) - Base unit for light items
- Kilogram (kg) - 1000 grams, base for body weight
- Metric ton - 1000 kg
Imperial System:
- Ounce (oz) - 1/16 of a pound
- Pound (lb) - Base unit
- Stone (st) - 14 pounds (UK)
- Ton - 2000 pounds (US)
Key Conversion Factors:
- 1 pound = 453.592 grams
- 1 kg = 2.205 pounds
- 1 ounce = 28.35 grams
- 1 stone = 6.35 kg
Currency Conversions Explained
Currency conversion involves exchanging one currency for another at current market exchange rates. Our converter supports 150+ world currencies with live rates updated hourly.
Popular Currency Pairs:
- USD to INR (US Dollar to Indian Rupee)
- EUR to USD (Euro to US Dollar)
- GBP to INR (British Pound to Indian Rupee)
- USD to EUR (US Dollar to Euro)
- INR to USD (Indian Rupee to US Dollar)
📐 Common Unit Conversion Formulas
Temperature Formulas
- Celsius to Fahrenheit: °F = (°C × 9/5) + 32
- Fahrenheit to Celsius: °C = (°F - 32) × 5/9
- Celsius to Kelvin: K = °C + 273.15
- Kelvin to Celsius: °C = K - 273.15
Length Formulas
- Inches to Centimeters: cm = inches × 2.54
- Feet to Meters: m = feet × 0.3048
- Miles to Kilometers: km = miles × 1.60934
- Meters to Feet: feet = meters × 3.28084
Weight Formulas
- Pounds to Kilograms: kg = lbs × 0.453592
- Kilograms to Pounds: lbs = kg × 2.20462
- Ounces to Grams: g = oz × 28.3495
- Grams to Ounces: oz = g × 0.035274
Speed Formulas
- km/h to mph: mph = km/h × 0.621371
- mph to km/h: km/h = mph × 1.60934
- m/s to km/h: km/h = m/s × 3.6
Volume Formulas
- Liters to Gallons (US): gallons = liters × 0.264172
- Gallons to Liters: liters = gallons × 3.78541
- ml to Cups: cups = ml × 0.00422675
Area Formulas
- Square Meters to Square Feet: sq ft = sq m × 10.7639
- Square Feet to Square Meters: sq m = sq ft × 0.092903
- Acres to Square Meters: sq m = acres × 4046.86
💼 Real-World Use Cases for Unit Converters
For Travelers
- Convert temperatures for weather forecasts (°C ↔ °F)
- Convert currency before international trips
- Convert distances on road signs (km ↔ miles)
- Convert weights for luggage limits (kg ↔ lbs)
For Students
- Convert units for homework and exams
- Understand scientific measurements
- Learn conversion factors
- Practice math problems
For Chefs & Bakers
- Convert oven temperatures (°F ↔ °C)
- Convert ingredient weights (grams ↔ ounces)
- Convert liquid volumes (cups ↔ ml)
- Use international recipes
For Fitness Enthusiasts
- Track body weight (kg ↔ lbs)
- Convert running distances (miles ↔ km)
- Monitor heart rate zones
- Calculate calorie burning rates
For Real Estate
- Convert property areas (sq ft ↔ sq m)
- Calculate land in acres or hectares
- Understand plot sizes
- Compare international properties
For Engineers & Scientists
- Precise measurements in projects
- Unit standardization
- Technical calculations
- Research and experiments
For Online Shoppers
- Convert product dimensions
- Understand international sizing
- Compare prices in different currencies
- Calculate shipping weights
Frequently Asked Questions
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