Which Is Bigger? Compare Two Measurements
Put in two amounts, even in different units, and see which is bigger and by how much. Or compare one size with things that are easier to picture, like football pitches and Olympic pools.
Enter two amounts. They can be in different units, such as 0.05 km and 5.5 m.
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Is 0.05 km more than 5.5 m? Is 5 m longer than 400 cm? Different units make a simple question awkward.
The human brain has no intuition for large quantities. This tool does two jobs. Compare two measurements converts both into the same unit and tells you which is bigger, by how many times, and by how much. Compare with everyday things turns one quantity into something you can picture: "2.6 million square kilometres" is a fact, "roughly 364 million football pitches" is something you can almost feel. The first is exact; the second is for illustration.
How we work it out
To compare two measurements, both are converted to a common base unit (metres, square metres, litres, kilograms or seconds) and divided, so 0.05 km against 5.5 m gives an exact ratio. Both must be the same kind of measure, so it won't compare a weight with a length. To compare one value with everyday things, it converts your number and shows the familiar references closest in size, leaving out anything more than about 20 times bigger or smaller, because those comparisons are not much use.
Common mistakes
- Comparing different units without converting. Make sure the units are right.
- Mixing up the order of the two amounts.
- Forgetting a bigger number is not always a bigger amount, such as in different currencies.
Questions
How do I compare two measurements in different units?
Choose "Compare two measurements", enter each amount and pick its unit. The tool converts both to the same base unit, such as metres, litres or kilograms, then tells you which is bigger, how many times bigger, and the difference. For example 0.05 km is 50 m, so it is about 9 times as long as 5.5 m.
Can I compare a length with a weight?
No. You can only compare two things of the same kind: two lengths, two areas, two volumes, two weights or two times. If you pick units of different kinds the tool tells you so.
Are the unit conversions exact?
Yes. They use the standard definitions: 1 inch is exactly 2.54 cm, 1 pound is exactly 0.45359237 kg, a UK gallon is exactly 4.54609 litres and a US gallon is 3.785411784 litres. A year is taken as 365.25 days.
How accurate are the reference sizes?
Reference values are approximate averages. A football pitch varies slightly between grounds; an Olympic pool has a defined volume but depth varies. These comparisons are for illustration, not precision measurement.
Why Wales?
Because comparing large areas to Wales is a proud tradition of British science journalism, and we are not going to be the ones to break it.
Comparisons done. Research resumes.