Is this calculator free to use?

Yes. The Unit Converter is free to use with no sign-up required. A free account adds more calculation history, multiple workspaces, and access to your saved data from any device.

Unit Converter | 14 Categories, Metric & Imperial, Free

Free unit converter with 14 categories: length, weight, volume (US & UK), power, force, temperature, and data

Convert inches to cm, lbs to kg, and more.

When Should You Use This Calculator?

Running fast single conversions in Simple mode
Using high-intent Popular Pairs for repeat conversions (lbs↔kg, in↔cm, etc.)
Parsing one-line text input like "12 in to cm" in Advanced mode
Converting power (horsepower↔kW) and force (Newtons↔pound-force) for engineering work
Distinguishing US from Imperial (UK) volume units, and network bit-rates from byte-based file sizes

Key Features:

Three modes: Simple, Popular Pairs, and Advanced
One-click high-intent conversion pairs with category presets
Advanced quick parser for one-line conversion input
Recent conversion pairs and fast swap workflow

Frequently Asked Questions

How do I convert inches to centimeters?

Multiply inches by 2.54. For example, 12 inches = 30.48 cm. You can also select Length in this converter, enter your value in inches, and select cm as the output unit for instant results.

How do I convert pounds to kilograms?

Multiply pounds by 0.453592. For example, 150 lbs = 68.04 kg. Use the Weight category and select lbs to kg for an instant conversion.

Are the conversions exact?

We use high-precision conversion factors. Results are typically accurate to 10+ decimal places, which is sufficient for almost all scientific and engineering needs.

What unit categories are supported?

The converter supports 14 categories: length, weight, temperature, area, volume, speed, data, pressure, energy, frequency, angle, time, power, and force. Pick a category, then expand the Popular Pairs section for one-click common conversions.

Why does 1 gallon give a different result for US and UK?

A US gallon (3.785 liters) and a UK/Imperial gallon (4.546 liters) are different sizes — the UK gallon is about 20% larger. The same applies to pints and fluid ounces. Volume units are labeled (US) or (UK) so you convert against the correct standard.

Why is my internet speed in Mbps different from my download size in MB?

Network speeds (Kbps, Mbps, Gbps) measure bits per second using decimal multiples of 1000, while file sizes (KB, MB, GB) measure bytes using binary multiples of 1024, and a byte is 8 bits. A "100 Mbps" connection downloads at roughly 12.5 MB per second, not 100 — use the Data category to convert between bit-based and byte-based units directly.

Can I export my Unit Converter calculations?

Yes. In guest mode you can export your calculations to JSON. Signing in adds PDF and CSV export. Click the export button to download your results — useful for record-keeping, sharing, or importing into other tools.

Does this calculator save my history?

Yes. Your calculation history is saved automatically. As a guest you can keep up to 50 calculations per workspace on your device. Sign in for free to keep up to 100 per workspace and access them from any device.

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