Unit Converter
Convert between 50+ unit types across length, weight, temperature, volume, speed, area, data size, and time. Results update in real time as you type.
Key features
- 50+ unit types across 8 useful categories
- Length, weight, temperature, volume, speed, and more
- Real-time conversion as you type in any field
- Supports both metric and imperial systems
Guide
Measurement units exist because different regions, industries, and historical traditions developed their own systems for quantifying the physical world. The metric system (SI) dominates science, medicine, and most countries. The imperial system persists in the United States, Myanmar, and Liberia, and also appears in British colloquial usage (miles, pints, stones). Various specialized units exist in cooking, shipping, aviation, and other fields. A unit converter eliminates the mental math and lookup tables required to move between these systems. The WebRecast unit converter covers eight categories with over 50 unit types: length, weight (mass), temperature, volume, speed, area, data size, and time. Each category allows conversion between any pair of supported units, with results updating in real time as you type. This immediate feedback is useful when you need quick answers during cooking, travel, construction, shopping, or technical work. Length conversions are among the most frequent. The core relationships: 1 meter = 3.28084 feet = 39.3701 inches. 1 kilometer = 0.621371 miles. 1 inch = 2.54 centimeters (exact). 1 mile = 1.60934 kilometers. 1 yard = 0.9144 meters (exact). 1 nautical mile = 1.852 kilometers (exact), used in maritime and aviation navigation because it corresponds to one minute of latitude. Practical applications: converting height between centimeters and feet/inches (175 cm = 5 feet 8.9 inches), converting driving distances between kilometers and miles for trip planning, and converting room dimensions between metric and imperial for international furniture purchases. Weight and mass conversions appear constantly in cooking, shipping, fitness, and everyday commerce. Core relationships: 1 kilogram = 2.20462 pounds. 1 pound = 453.592 grams. 1 ounce = 28.3495 grams. 1 stone = 6.35029 kilograms = 14 pounds (used in the UK for body weight). 1 metric ton = 1,000 kilograms = 2,204.62 pounds. 1 troy ounce = 31.1035 grams (used for precious metals like gold and silver). Practical applications: converting body weight between kilograms, pounds, and stones for international health resources; converting recipe ingredients between grams and ounces; checking luggage weight limits when airlines specify in kilograms and your scale reads in pounds. Temperature conversion uses formulas rather than simple multiplication factors, making it harder to do mentally. Celsius to Fahrenheit: F = (C x 9/5) + 32. Fahrenheit to Celsius: C = (F - 32) x 5/9. Celsius to Kelvin: K = C + 273.15. Key reference points: water freezes at 0C / 32F / 273.15K. Water boils at 100C / 212F / 373.15K. Normal human body temperature is approximately 37C / 98.6F. Room temperature is roughly 20-22C / 68-72F. The two scales intersect at -40 (both -40C and -40F are the same temperature). Practical applications: adjusting oven temperatures in recipes from American food blogs (350F = 177C, 375F = 190C, 400F = 204C, 425F = 218C); understanding weather forecasts when traveling internationally; converting fever readings between thermometer types. Volume conversions are particularly confusing because the US customary system and the imperial system use the same names (gallon, pint, cup) for different volumes. 1 US gallon = 3.78541 liters. 1 imperial gallon = 4.54609 liters. 1 US cup = 236.588 milliliters. 1 US fluid ounce = 29.5735 milliliters. 1 liter = 33.814 US fluid ounces. 1 tablespoon = 14.787 milliliters (US). Additional units include teaspoons (4.929 mL US), pints (473.176 mL US), quarts (946.353 mL US), and cubic centimeters (1 cc = 1 mL exactly). Cooking is the primary domain for volume conversions, and getting them wrong can ruin a recipe. A US cup of flour (236 mL) and a metric cup (250 mL) differ by about 6%, which matters in baking where precision counts. Speed conversions matter for driving, running, cycling, and weather. 1 kilometer per hour (km/h) = 0.621371 miles per hour (mph). 1 m/s = 3.6 km/h. 1 knot = 1.852 km/h = 1.15078 mph. Common conversions: 100 km/h = 62.1 mph (highway speed in many countries), 130 km/h = 80.8 mph (motorway speed in France and Turkey), and a 5-minute kilometer running pace = 12 km/h = 7.46 mph. Speed limits, vehicle speedometers, and fitness tracking apps may use different units depending on the manufacturer's region, making quick conversion essential for travelers and athletes. Area conversions come up in real estate, agriculture, construction, and land management. 1 square meter = 10.7639 square feet. 1 hectare = 10,000 square meters = 2.47105 acres. 1 acre = 4,046.86 square meters = 43,560 square feet. 1 decare (donum in Turkish) = 1,000 square meters = 0.1 hectares. 1 square kilometer = 100 hectares = 247.105 acres. In Turkey, land is commonly measured in decares (donum), while international real estate uses square meters, hectares, or acres. A 150 square meter apartment is 1,614.6 square feet. A 5-decare farm field is 0.5 hectares or 1.236 acres. Data size conversions are essential in computing, networking, and digital storage. The binary system: 1 byte = 8 bits. 1 kilobyte (KB) = 1,024 bytes. 1 megabyte (MB) = 1,024 KB = 1,048,576 bytes. 1 gigabyte (GB) = 1,024 MB. 1 terabyte (TB) = 1,024 GB. Note: storage manufacturers and some software use decimal definitions (1 KB = 1,000 bytes, 1 MB = 1,000,000 bytes), which is why a "500 GB" hard drive shows approximately 465 GB in your operating system. The converter handles these conversions precisely. Practical applications: understanding how many photos (approximately 3 MB each) fit on a 64 GB memory card (roughly 21,000), calculating how long a 4 GB file takes to download at a given internet speed, and comparing cloud storage plans. Time conversions seem straightforward but have their complexities. 1 day = 24 hours = 1,440 minutes = 86,400 seconds. 1 week = 168 hours. 1 year = 365.25 days (accounting for leap years) = 8,766 hours. Converting between seconds, minutes, hours, days, and weeks is useful for project planning, billing (converting hourly rates to daily or annual figures), and calculating durations. How many hours are in 90 days? 90 x 24 = 2,160 hours. If a contractor bills at $85/hour, what is the daily rate for an 8-hour day? $680. What is the annual rate for 260 working days? $176,800. The unit converter is designed for speed and convenience. Select a category, choose your source and target units, type a number, and see the result immediately. There is no need to remember conversion factors, look up formulas, or chain multiple calculations together. The tool handles the math precisely, including the non-linear temperature conversions that trip people up. Practical scenarios demonstrate the converter's daily utility. You are shopping online from a US retailer and the product dimensions are listed as 24 x 18 x 12 inches. Convert to centimeters: 60.96 x 45.72 x 30.48 cm. Will it fit in your cabinet? You can answer that question in seconds. You are training for a 10K race and your running app shows pace in minutes per mile, but your training plan uses minutes per kilometer. Convert 8:30 per mile to approximately 5:17 per kilometer. You are baking a cake from a British recipe that calls for 12 ounces of flour. Convert to grams: 340 grams. Your bathroom scale reads in pounds but your doctor uses kilograms. Convert 172 pounds to 78.0 kg. For professional use, the converter supports units commonly needed in engineering (nautical miles, knots, troy ounces), agriculture (decares, hectares), computing (bytes through terabytes), and international trade (metric tons, imperial gallons). The breadth of supported units means you are unlikely to encounter a common conversion that the tool cannot handle. International shipping and e-commerce create constant unit conversion needs. Package dimensions and weights listed in inches and pounds on US sites need metric equivalents for customs forms and delivery estimates. Shipping carriers charge by dimensional weight, calculated as (Length x Width x Height) / 5000 in metric (cm and kg). If a package is 60 x 40 x 30 cm, its dimensional weight is 72,000 / 5000 = 14.4 kg. If the actual weight is 8 kg, the carrier charges based on 14.4 kg. If you are reading product specs in inches, converting to centimeters first and then computing dimensional weight avoids the error-prone step of converting the divisor. Construction and home improvement projects are a conversion-intensive domain. Lumber dimensions in the US use nominal sizes that differ from actual sizes (a "2x4" is actually 1.5 x 3.5 inches, or 38 x 89 mm). Tile sizes are commonly listed in inches in US markets (12x12, 18x18, 24x24 inches) and in centimeters in European and Turkish markets (30x30, 45x45, 60x60 cm). Paint coverage is specified in square feet per gallon in the US and square meters per liter in metric countries. A gallon of paint covers approximately 350 to 400 square feet (32.5 to 37.2 square meters). Converting between these specifications ensures you buy the right amount of material regardless of which market's products you are using. Fitness and health contexts generate frequent conversion needs beyond body weight. Running distances (5K = 3.1 miles, 10K = 6.2 miles, half marathon = 13.1 miles = 21.1 km, marathon = 26.2 miles = 42.195 km) are commonly referenced in both systems. Gym equipment may show weights in pounds (common in the US and some commercial gyms worldwide) or kilograms (standard in Olympic lifting and most international gyms). A 45-pound barbell plate is 20.41 kg, and a 20 kg plate is 44.09 pounds. Swimmers often need to convert between yards (common in US pools) and meters (used in international competition). A 25-yard pool is 22.86 meters, and times swum in short-course yards pools are not directly comparable to times in 25-meter or 50-meter pools. Cooking presents some of the most error-prone conversion situations because slight differences affect the final product. Butter measurements are a common source of confusion. In the US, butter is sold in sticks (1 stick = 113g = 4 oz = 1/2 cup). European recipes call for butter by weight (grams), while American recipes often use volume (cups, tablespoons). One tablespoon of butter is 14.18g or 0.5 oz. Converting a recipe that calls for 125g of butter: that is approximately 1 stick plus 1 tablespoon, or about 4.4 ounces. Getting this wrong by even 20% can noticeably affect the texture of baked goods. Medical contexts require precise conversions. Drug dosages are calculated in milligrams per kilogram of body weight. If a medication is prescribed at 10 mg/kg and the patient weighs 154 pounds, you first convert to kilograms (154 / 2.20462 = 69.85 kg), then calculate the dose (69.85 x 10 = 698.5 mg). Blood glucose readings in the US use mg/dL (milligrams per deciliter), while most other countries use mmol/L (millimoles per liter). The conversion factor is: mmol/L = mg/dL / 18.018. A reading of 126 mg/dL equals 7.0 mmol/L. Blood pressure is universally measured in mmHg (millimeters of mercury), but height for BMI calculations may be in feet/inches or centimeters depending on the country. Travel between metric and imperial countries generates a cascade of conversion needs. Renting a car in the US means reading a speedometer in mph, buying fuel in gallons, and measuring distances in miles. Returning to Turkey means switching everything back to km/h, liters, and kilometers. Temperature adds another layer: a weather forecast of 68F in New York is 20C, and a forecast of 95F is 35C. The unit converter on your phone or browser tab handles all of these switches without the mental overhead of remembering conversion factors under jet-lag conditions. Scientific and engineering work often requires conversions between SI base units and derived units. Pressure can be expressed in pascals, atmospheres, bars, millibars, millimeters of mercury (mmHg), pounds per square inch (PSI), or torr. Energy can be in joules, calories, kilocalories, kilowatt-hours, or British thermal units. Force can be in newtons, dynes, kilograms-force, or pounds-force. While the WebRecast converter focuses on the most commonly needed everyday conversions, understanding the general principle of unit conversion (multiply by the appropriate conversion factor, or divide by its inverse) enables you to handle any conversion when you know the factor. Bookmark the unit converter and reach for it whenever two measurement systems collide. It saves more time than you expect, eliminates rounding errors from mental math, and handles the tricky conversions (temperature, volume differences between US and imperial) that are genuinely difficult to do in your head. The tool runs in your browser, requires no account or installation, and produces instant results. Common conversion mistakes worth avoiding include confusing fluid ounces (a volume measurement) with ounces (a weight measurement). A fluid ounce of water weighs approximately one ounce, but this equivalence breaks down for other substances. A fluid ounce of honey weighs about 1.5 ounces because honey is denser than water. A fluid ounce of cooking oil weighs about 0.8 ounces because oil is less dense. When a recipe calls for ounces, check whether it means weight or volume, as using the wrong type produces incorrect amounts. The difference between US and imperial measurements trips up anyone who cooks from both American and British recipes. A US pint is 473 mL while an imperial pint is 568 mL, a 20% difference. A US cup is 236 mL while an imperial cup (now rarely used) was 284 mL. A US gallon is 3.785 liters while an imperial gallon is 4.546 liters. If a British recipe calls for a pint of milk and you use a US pint, you are short by nearly 100 mL, which can matter in baking and custard-making. The unit converter specifies US or imperial for each volume unit, preventing this confusion. Precious metals use a separate weight system (troy weight) that predates the metric system and is still used globally in gold, silver, and platinum trading. A troy ounce is 31.103 grams, while a standard (avoirdupois) ounce is 28.350 grams. A troy ounce is about 10% heavier than a regular ounce. Conversely, a troy pound contains only 12 troy ounces (373.24 grams), while a regular pound contains 16 avoirdupois ounces (453.59 grams), so a troy pound is actually lighter than a regular pound. If gold is priced at $2,000 per troy ounce, the price per regular ounce is $2,000 x 28.350 / 31.103 = $1,823. These distinctions matter for anyone investing in precious metals or comparing prices. Fabric and textile measurements vary between countries. Fabric in Turkey and most of Europe is sold by the meter (running meter at a standard bolt width, typically 140 to 150 cm). In the US, fabric is sold by the yard (91.44 cm), and bolt widths vary more widely (36 to 60 inches, or 91 to 152 cm). If a sewing pattern calls for 3 yards of 45-inch-wide fabric, you need 2.74 meters of 114 cm fabric. But if the Turkish store sells 150 cm wide fabric, you may need less length because the wider bolt provides more usable area. The length conversion (yards to meters) is the first step, and the width difference may require pattern layout recalculation. Paper sizes present a conversion challenge for anyone working across international boundaries. The A4 paper standard (210 x 297 mm, used globally except in North America) differs from US Letter size (8.5 x 11 inches = 215.9 x 279.4 mm). A4 is slightly narrower and slightly taller than Letter. Documents formatted for A4 may not print correctly on Letter paper and vice versa. Legal size (8.5 x 14 inches = 215.9 x 355.6 mm) is close to the A4-derived Folio size but not identical. While these are not unit conversions in the traditional sense, the underlying measurements involve the same inch-to-millimeter conversions that the unit converter handles. Energy unit conversions matter for anyone tracking nutrition across different label formats, managing utility bills, or understanding scientific literature. Food energy is measured in kilocalories (kcal, commonly written as Calories with a capital C) in most countries, but in kilojoules (kJ) on Australian and some European food labels. 1 kcal = 4.184 kJ. A food item labeled as 840 kJ contains 200.8 kcal. Electricity consumption is measured in kilowatt-hours (kWh), where 1 kWh = 3,600,000 joules = 3,600 kJ. Your monthly electricity bill of 300 kWh represents 1,080,000 kJ of energy. Natural gas is measured in cubic meters (m3) on Turkish utility bills, where 1 m3 of natural gas contains approximately 10.55 kWh of energy. Converting between these energy units helps you compare costs across different fuel types for heating or cooking. Map scales and geographic distances involve unit conversions that travelers and students encounter regularly. A map at 1:50,000 scale means that 1 cm on the map represents 50,000 cm (500 meters or 0.5 km) on the ground. A distance of 4 cm on the map represents 2 km in reality. If you are working with an older map in miles, 1 mile on the map at the same scale would represent the same physical distance, but you need to convert between the map's measurement system and the units you use for navigation. The history of measurement systems explains why conversion is still necessary in the 21st century. The metric system was created during the French Revolution in the 1790s to standardize the chaotic mix of local measurement systems across France. It spread globally through colonialism, trade, and scientific consensus. The US customary system derives from English units that predated the metric system and persisted due to the practical costs of conversion in an established industrial economy. Turkey adopted the metric system in 1933 as part of Ataturk's modernization reforms, but older rural measurements (like the donum for land area) persist in common usage alongside their metric equivalents. Understanding this history explains why the world has not yet unified on a single system and why unit converters remain essential everyday tools.
Frequently asked questions
Can I convert Celsius to Fahrenheit?
Yes. Select Temperature, enter your value, and the result appears instantly.
Do you support digital data units?
Yes. The tool converts between bytes, kilobytes, megabytes, gigabytes, and terabytes.
