### Instructions

The significant figures calculator is not working as it should. It should be displayed above but it isn’t. So, apologies, please try the calculator at this link instead.

There, you will enter the number that you wish to round to a given number of significant figures. E.g. enter 12345.678 and ask to round to four sig figs, the answer will be 12350.

When converting or manipulating measurements, your final result is

only as significant as your least significant value. So, if you see a phrase like “5 kg (or 11.023113 lbs)” that’s just plain wrong. The original kg value has only a single sig fig and so the conversion should only be given to one sig fig too, i.e. 5 kg is about 10 lbs.

When you’ve finished doing your sig figs calcs why not take the chance to subscribe to NASA’s free Tech Briefs magazine, which offers newsbytes and features on all the math and engineering, science, and technology happening at NASA right now.