Unit · Format · Data · Color · Speed
Convert Tools Online
Free Online File & Format Conversion — Fast, Private, Browser-Based
Length Converter
Convert between meters, feet, inches, miles, km and more.
Weight & Mass Converter
Convert between kilograms, pounds, ounces, grams and more.
Temperature Converter
Convert between Celsius, Fahrenheit and Kelvin.
Color Converter
Convert colors between HEX, RGB, HSL and CMYK formats.
Data Storage Converter
Convert between bytes, KB, MB, GB, TB and more.
Speed Converter
Convert between km/h, mph, m/s, knots and Mach.
Why Use Convert Tools Online?
Accurate & Reliable
All conversions are based on internationally recognized standards and definitions. Results match authoritative references for everyday and professional use.
Instant Results
Conversions happen as you type with no submit button required. Switch units in real time and see updated results immediately.
Free, Always
No account, no subscription, no usage limits. Every converter is free for personal and commercial use with no strings attached.
Private by Design
All calculations happen locally in your browser. No input data is transmitted to servers or logged anywhere.
SI & Imperial Units
Covers both metric (SI) and imperial/US customary systems. Convert between any combination of units with full precision.
Works on Any Device
Fully responsive layout works on desktop, tablet, and mobile. Use in the field, in the lab, or at your desk — no app installation needed.
How to Use Our Converters
Choose a Converter
Select the category you need — length, weight, temperature, color, data storage, or speed.
Enter Your Value
Type the number you want to convert and select the source unit from the dropdown. Results update instantly.
Read or Copy the Result
See converted values across all target units at once. Click to copy any result directly to your clipboard.
Who Uses Convert Tools Online?
Convert between metric and imperial units for measurements, material specifications, and technical calculations.
Convert weight and volume units between US cups, grams, and ounces for recipes from different culinary traditions.
Convert units for physics, chemistry, and maths assignments. Cross-check textbook values quickly without a calculator.
Convert color formats between HEX, RGB, and HSL for CSS. Convert data storage units when working with file systems and APIs.
Frequently Asked Questions
How accurate are the conversions?
Our conversions use internationally recognized definitions and standards. For everyday and professional use the results are precise. For safety-critical applications, always verify with an authoritative reference.
Are these converters free to use?
Yes, completely free with no account, no subscription, and no usage limits.
Why might my result differ from another converter?
Minor differences can arise from rounding precision or the specific unit definition used (e.g., US fluid ounce vs. imperial fluid ounce). We display which standard is used on each tool page.
Do you support both metric and imperial units?
Yes. All converters support both SI (metric) and imperial/US customary units, and you can convert between any combination.
Is my data sent to your servers?
No. All conversions are computed locally in your browser. Your input is never transmitted to any server.
Can I use these tools on mobile?
Yes. All converters are fully responsive and work on any modern mobile browser.