Free Online Unit Converter — 12 Categories and 100+ Units
Need to convert meters to feet, kilograms to pounds, or Celsius to Fahrenheit? Unit Converter by Neonway is a free, browser-based tool that handles all of those conversions — and dozens more — without any software to install or account to create. Open it in your browser and start converting immediately.
With 12 conversion categories and more than 100 units, this tool covers everything from everyday kitchen and travel conversions to specialist categories like fabric weight and fuel economy. The interface is clean, fast, and distraction-free — a single screen with instant results.
What Can You Convert?
The converter is organized into 12 clearly labeled categories, each covering the most useful units for that measurement type.
Length covers everything from a Mil (one-thousandth of an inch) through Point, Pica, Inch, Foot, Yard, Mile, Nautical Mile, and the full metric range from Millimeter to Kilometer. Area includes Square Inch, Square Foot, Square Yard, Acre, Square Mile, Hectare, and Square Kilometer. Time spans from Nanosecond and Microsecond all the way up to Decade and Century.
Temperature handles Celsius, Fahrenheit, and Kelvin using the correct formulas — not linear approximations. Weight covers US and UK units (Ounce, Troy Ounce, Pound, Stone, Short Ton, Long Ton) alongside metric (Milligram, Gram, Kilogram, Metric Ton). Volume is the most comprehensive category, with a complete US liquid set, a full Imperial set, and metric units including Liter, Milliliter, and Cubic Meter.
Speed includes mph, km/h, m/s, knots, and feet per second. Power covers Watt, Kilowatt, Megawatt, Electric and Metric Horsepower, and BTU per minute. Pressure handles Pascal, Bar, Atmosphere, PSI, inHg, mmHg, and Torr. Energy converts between Joule, Calorie, Kilocalorie, Watt-hour, kWh, BTU, and Electronvolt.
Two specialist categories round out the tool. Fabric converts between g/m² (GSM) and oz/yd² (OSY) — essential for textile and apparel work. Fuel Economy converts between km/L, L/100km, US MPG, and UK MPG using the correct inverse-formula math, since these units are not linearly proportional.
Instant Results With Flexible Output Options
The converter updates its result live as you type — there is no submit button to click and no delay. What sets it apart from basic converters is the range of output formatting options available in the settings drawer.
Results can be shown as a standard decimal, as a fraction, or as both at the same time. Fraction denominators go up to 128, covering the fine precision needed for woodworking, machining, and other trades. You can set the decimal precision from 0 to 8 places using pill buttons — useful when you need a rough estimate or a highly exact figure. A thousands separator toggle makes large numbers easy to read at a glance, and scientific notation kicks in automatically for values beyond the normal display range.
Flip, Copy, and Work Faster
The flip button reverses the source and target units in one click. With the Carry Value option enabled in settings, it also places the converted result back into the input field — so you can chain conversions without retyping. The Copy button sends the result to your clipboard instantly, with an option to include the unit label alongside the number.
Power users can skip the mouse entirely. Press F to flip units, F11 to toggle fullscreen, ⌘, to open settings, and Esc to close any open panel.
Display and Theme Options
The app supports dark mode, light mode, and a system-auto setting that follows your operating system preference. The settings drawer also gives you control over fraction input parsing — enabling you to type values like “3 1/2” or “7/8” directly into the input field rather than converting them yourself. All your preferences and your last-used category and units are saved automatically in your browser between sessions.
How to Use the Unit Converter
- Open the tool in your browser — it loads instantly with no splash screen.
- Click the category dropdown at the top and select the type of measurement you want to convert.
- Choose your source unit from the From dropdown on the first card.
- Choose your target unit from the To dropdown on the second card.
- Type your value into the input field — the result appears instantly.
- Click Copy to send the result to your clipboard, or press F to flip units.
- Open the settings drawer (gear icon or ⌘,) to adjust decimal places, display format, theme, and more.
Why Choose This Unit Converter?
- Free and instant — no download, no installation, no payment.
- No sign-up required — open the URL and start converting immediately.
- 12 categories, 100+ units — more coverage than most basic converters.
- Fraction display and input — unique among browser-based converters.
- Precise output control — choose 0–8 decimal places at a tap.
- Works on any device — desktop, laptop, tablet, or phone.
- Privacy-safe — all conversions happen locally; no data is sent to any server.
- Dark and light themes — including an automatic system-preference mode.
- Keyboard shortcut support — fast and efficient for power users.
- Specialist categories — fabric weight and fuel economy go beyond what generic converters offer.
Frequently Asked Questions
Is this unit converter completely free?
Yes. Unit Converter by Neonway is entirely free to use in any modern browser, with no subscriptions or hidden fees.
Do I need to create an account?
No. The tool works immediately without any sign-up. Your settings and last-used units are saved automatically in your browser’s local storage.
Does it work on mobile devices?
Yes. The app is fully responsive and works on phones and tablets as well as desktop and laptop screens.
How many units does it support?
More than 100 units across 12 categories, including both US/Imperial and metric systems for most measurement types.
Can I enter fractions as input?
Yes. Enable the Fraction Input option in settings, then type values like “3 1/2” or “7/8” directly into the input field.
Is my data private?
Yes. All conversions are calculated locally in your browser. No input values or results are sent to any server.
Ready to convert? Open Unit Converter by Neonway in your browser and get your answer in seconds — no download required.
