How do I convert cm to inches?

Multiply centimeters by 0.393701. For example, 10 cm = 3.937 inches.

How do I convert kg to lbs?

Multiply kilograms by 2.20462. For example, 70 kg = 154.32 lbs.

What is the formula for Celsius to Fahrenheit?

°F = (°C × 9/5) + 32. For example, 100°C = 212°F.

How many cups in a liter?

There are approximately 4.227 US cups in 1 liter.

How do I convert miles to kilometers?

Multiply miles by 1.60934. For example, 5 miles = 8.047 km.

What is a gas mark in Celsius?

Gas Mark 1 = 140°C (275°F). Each gas mark increment adds roughly 14°C (25°F).

How do I calculate BMI?

BMI = weight(kg) / height(m)². A healthy BMI is between 18.5 and 24.9.

ConvertAll

Fast, free unit conversions that update as you type. No sign-up, no clutter — just answers.

📏

Length

cm, inches, feet, miles, km

⚖️

Weight

kg, lbs, grams, stone

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Temperature

°C, °F, Gas Mark

🥛

Volume

liters, gallons, cups, ml

🚗

Speed

mph, km/h, knots

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Area

sq ft, sq m, acres

🍳

Cooking

Cups to grams, oven temps

🔨

Construction

Concrete, paint, tile

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Fitness

BMI, pace, calories

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Clothing

Shoe, dress, ring sizes

Frequently Asked Questions

How do I use ConvertAll?

Simply click on any conversion category or use the search bar. Enter a value and the result updates instantly as you type. No submit button needed!

Are the conversions accurate?

Yes! We use standard conversion factors from the International System of Units (SI). You can toggle between 2 and 10 decimal places for extra precision.

Is ConvertAll free?

Completely free. No sign-up, no subscription, no hidden costs. We're ad-supported to keep the lights on.

Can I use this on my phone?

Absolutely! ConvertAll is fully responsive and works great on phones, tablets, and desktops.

How do I convert cups to grams for cooking?

Use our Cooking Hub! Select an ingredient from the dropdown — different ingredients have different weights per cup. Flour is 120g/cup, sugar is 200g/cup, butter is 227g/cup, and so on.

What is a Gas Mark?

Gas Mark is a temperature scale used on gas ovens in the UK and some Commonwealth countries. Gas Mark 1 = 275°F (140°C), and each mark increases by about 25°F (14°C).

How do I convert between US and EU shoe sizes?

Check our Clothing Size Hub! We have full conversion tables for men's, women's, and kids' shoe sizes across US, EU, and UK systems.

How do I calculate how much concrete I need?

Use our Construction Hub's Concrete Calculator. Enter your slab dimensions (length, width, depth) and we'll calculate cubic yards and estimate the number of bags needed.

Can I copy the conversion result?

Yes! Click the 📋 copy icon next to any result to copy it to your clipboard instantly.

Do you store my data?

No. All conversions happen in your browser. We don't send your inputs to any server, and we don't track individual conversions.