Unit Converter - 単位変換ツール

単位変換ツール:長さ・重さ・温度・体積・面積・速度・データ。入力と同時に結果を表示、単位の入れ替え、コピー、履歴に対応。

Unit Converter - Length, Weight & Temperature Tool Unit Converter turns any measurement into the unit you need while you type. Open the popup, enter a number, choose the units — the result appears instantly and is recalculated on every keystroke. This unit converter computes everything locally inside the extension: no account, no tracking, not a single network request. The only permission it uses is local storage, which keeps your recent conversions and your last-used units. SEVEN CATEGORIES IN ONE UNIT CONVERTER • Length converter — millimeters, centimeters, meters, kilometers, inches, feet, yards, miles • Weight and mass — milligrams, grams, kilograms, tonnes, ounces, pounds, stones • Temperature converter — Celsius, Fahrenheit and Kelvin with exact formulas • Volume — milliliters, liters, cubic meters, teaspoons, tablespoons, cups, pints, gallons (US and UK) • Area — square meters, hectares, square kilometers, square feet, acres • Speed — meters per second, km/h, mph, knots, feet per second • Data — bits, bytes, KB, MB, GB, TB, plus binary KiB, MiB and GiB KEY FEATURES 🔢 Live results: the unit converter recalculates the moment a digit changes 🔁 Swap button flips the unit converter's direction in one click 📋 Copy button puts the converted measurement on your clipboard, unit symbol included 🕘 History keeps your ten most recent conversions — click one to load it back 📐 A rate line such as "1 mi = 1.609344 km" shows the ratio behind every result 🌡️ Real Celsius–Fahrenheit–Kelvin formulas, so −40 °C equals −40 °F 🌐 Interface localized into 33 languages HOW TO CONVERT UNITS IN THREE STEPS 1. Click the Unit Converter icon and pick a category — length, weight, temperature, volume, area, speed or data. 2. Type a number and select the "from" and "to" units; this metric converter shows the result as you type. 3. Press Copy, or hit the swap button to convert units in the opposite direction. Your last category, units and value are saved locally, so the unit converter reopens exactly where you left off. WHY THE NUMBERS CAN BE TRUSTED 1. Every factor comes from the exact international definitions: 1 inch = 25.4 mm, 1 pound = 453.59237 g. 2. Temperature conversion uses the proper formulas, never a linear shortcut that breaks below zero. 3. Results keep up to 12 significant digits and strip floating-point noise, so 0.1 + 0.2 is shown as 0.3. 4. Data units separate decimal (KB, MB, GB) from binary (KiB, MiB, GiB): 1 GiB = 1.073741824 GB. 5. The engine of this unit converter is an isolated module covered by an automated suite of 43 checks. ONE UNIT CONVERTER INSTEAD OF A SEARCH TAB A measurement question usually means opening a search page, finding a converter site, closing banners and retyping the number. This unit converter removes the detour: the popup opens already focused on the value field, and the conversion happens as the digits appear. For repeated work, the history brings any earlier measurement back in one click. FAQ Q: Does this unit converter work offline? A: Yes. Every conversion is computed inside the popup; nothing is fetched from the internet, ever. Q: How accurate is the temperature converter? A: It applies the exact formulas between Celsius, Fahrenheit and Kelvin, so values like body temperature (37 °C = 98.6 °F) come out precisely. Q: Can this measurement tool convert units of digital data? A: Yes. It handles bits, bytes and both decimal and binary multiples, which is handy when a drive's advertised GB differs from the GiB your system reports. Q: Where does the unit converter store my conversion history? A: In your browser's local extension storage. It never leaves your device, and one click clears it. Q: Does the unit converter handle both metric and imperial systems? A: Yes, in both directions: use it as a metric converter for inches to centimeters, or go the other way from kilograms to pounds. WHO USES UNIT CONVERTER • Students checking measurement homework in physics, chemistry and math • Cooks converting cups, tablespoons and milliliters mid-recipe • Travelers translating miles, Fahrenheit and gallons into familiar units • Developers and admins moving between MB, MiB and GB without a calculator • Engineers and makers who need a length converter from imperial drawings to metric parts Install Unit Converter, and the next time a measurement arrives in the wrong unit, the answer is two clicks away: open the popup, type the number, and read the converted unit — computed on your own machine.