Question 1

How accurate are these conversions?

Accepted Answer

Our conversions use standard internationally recognised conversion factors. They're accurate enough for everyday use but not intended for scientific or engineering precision work. For critical applications, always verify with certified measurement tools.

Question 2

What's the difference between metric and imperial?

Accepted Answer

Metric is based on powers of 10 (metres, kilograms, litres) and is used by most of the world. Imperial uses various bases (feet/inches, pounds/ounces) and is primarily used in the US, UK (partially), and a few other countries. Metric makes calculations easier; imperial is often more intuitive for certain everyday measurements.

Question 3

Why are there two types of gallons?

Accepted Answer

The US gallon (3.785 litres) and UK/Imperial gallon (4.546 litres) are different historical standards. The UK redefined the gallon in 1824, while the US kept the older English wine gallon. Always check which gallon a recipe or fuel economy figure uses — the UK gallon is about 20% larger.

Question 4

Do you save my conversions?

Accepted Answer

We only save your unit preferences locally in your browser to remember your last-used units. This data never leaves your device. No conversion data is stored on our servers or transmitted anywhere.

Question 5

What's the difference between KB and KiB?

Accepted Answer

KB (kilobyte) typically means 1,000 bytes in storage contexts (decimal/SI standard). KiB (kibibyte) always means exactly 1,024 bytes (binary/IEC standard). Storage manufacturers use KB/GB, while operating systems often use KiB/GiB internally. This explains why your hard drive shows less space than advertised.

Question 6

How do I convert Celsius to Fahrenheit?

Accepted Answer

Multiply the Celsius temperature by 9/5 (or 1.8) and add 32. For example: 20°C × 1.8 + 32 = 68°F. For a quick estimate, double the Celsius value and add 30. Or simply use our temperature converter for instant, accurate results.

Question 7

Why can't Kelvin be negative?

Accepted Answer

Kelvin starts at absolute zero (0 K = -273.15°C), the coldest possible temperature where all molecular motion theoretically stops. By definition, you cannot have less than zero molecular motion, so negative Kelvin temperatures don't exist.

Question 8

Are cooking cups the same everywhere?

Accepted Answer

No. US cups are 236.6ml, UK cups are 284ml (though rarely used now), and Australian/metric cups are 250ml. Most modern recipes use US cups unless from Australia/New Zealand. When precision matters for baking, weighing ingredients in grams is always more reliable.

Question 9

Why does my hard drive show less space than advertised?

Accepted Answer

Storage manufacturers use decimal units (1 GB = 1,000,000,000 bytes) while operating systems display binary units (1 GiB = 1,073,741,824 bytes). A '1 TB' drive actually contains about 931 GiB. You're not missing any space — it's just measured differently.

Question 10

What's the difference between a US and UK pint?

Accepted Answer

A US pint is 473ml (16 US fluid ounces), while a UK pint is 568ml (20 UK fluid ounces). The UK pint is about 20% larger. This is why British beer glasses are larger than American ones!

Question 11

How do I convert running pace between min/km and min/mile?

Accepted Answer

To convert min/km to min/mile, multiply by 1.609. To convert min/mile to min/km, divide by 1.609. For example, 5:00 min/km = 8:03 min/mile. A quick estimate: add about 60% to your min/km pace to get min/mile.

Question 12

Can I use the reference tables offline?

Accepted Answer

Yes! Use the Print button on any table page to print it or save it as a PDF. The tables are formatted for clean printing with appropriate sizing. You can also install our app (Add to Home Screen) for offline access to the converters.

Question 13

Why are US and UK fluid ounces different?

Accepted Answer

US fluid ounces (29.57ml) and UK fluid ounces (28.41ml) evolved from different historical standards. The UK redefined its measurements in 1824. Paradoxically, UK fluid ounces are smaller, but there are more of them in UK pints and gallons, making UK volumes larger overall.

Question 14

Is this converter free to use?

Accepted Answer

Yes, completely free! We're ad-supported, which allows us to provide accurate unit conversions at no cost. We don't require registration, don't sell your data, and don't limit how many conversions you can do.

Question 15

What units does a stone represent?

Accepted Answer

One stone equals 14 pounds (approximately 6.35 kg). It's commonly used in the UK and Ireland for body weight. To convert: divide your weight in pounds by 14 to get stones. For example, 168 lbs = 12 stone exactly.

Question 16

Can I use these tools offline?

Accepted Answer

Yes! ConvertIt is a Progressive Web App (PWA), which means you can install it on your device for offline access. On mobile, tap 'Add to Home Screen' in your browser menu. On desktop, look for the install icon in your browser's address bar. Once installed, all converters work without an internet connection.

Question 17

Why do the US and UK use different measurement systems?

Accepted Answer

The UK officially adopted metric in 1965 but imperial units persist in daily life due to tradition. The US never officially adopted metric because of the high cost of switching infrastructure and cultural resistance. Both countries use a mix of systems — the US uses metric in science and medicine, while the UK uses miles for roads but litres for fuel.

Question 18

How precise are decimal places in the results?

Accepted Answer

Our converter displays up to 6 significant figures, which is more than sufficient for everyday conversions. For most practical purposes (cooking, DIY, fitness), 2-3 decimal places are plenty. Scientific work may require specialised tools with higher precision and uncertainty calculations.

Frequently Asked Questions

Still have questions?

Learn More

Metric vs Imperial Guide

Data Storage Units Explained