Significant Figures Calculator

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.

13 Comments

13 responses so far ↓

sara lohse // Oct 22, 2008 at 5:12 pm

wheres the calculator?!
David Bradley // Oct 22, 2008 at 6:42 pm

Right there, below the words “Significant Figures Calculator” You enter the number you want to round in the box below the word “Number” and fill in the options in the two boxes below. Click “Go” and the big box on the right of the calculator will display your number to the appropriate number of sig figs. Nothing could be simpler. It’s not a calculator in the sense of a scientific calculator
zak // Nov 4, 2008 at 1:18 pm

where is the calculator?????
David Bradley // Nov 4, 2008 at 2:40 pm

Zak…you’re only the second person to ask this question in the two years since I installed the calculator. I’m really not sure how to respond. The calculator is right there at the top, just below the phrase Significant Figures Calculator. If you’re looking for a keypad type input, it ain’t there, just enter your number to round and click go. Isn’t it obvious?
stan // Nov 13, 2008 at 7:27 am

I mean no offense, but it seems your calculator doesn’t appear on some browsers. Possibly mozilla vs IE? I use IE. Maybe it’s relatively recent, as the first comment is Oct 22. It does not display on mine. Popup blocker perchance?
David Bradley // Nov 13, 2008 at 8:37 am

Hoist by my own petard. Yes, I see where you’re all coming from now…will investigate. Works perfectly in Firefox, to which I recommend all IE users switch if they can!
JP // Jan 6, 2009 at 10:12 pm

yeah i cant see it either…..
Sue // Jan 22, 2009 at 12:29 am

Where’s the calculator?!
Firefox users are discriminated against!
David Bradley // Jan 22, 2009 at 7:51 am

Sue, I’ve tried to fix this. I’m an FF user myself. Let me take another look.
Tom // Jan 22, 2009 at 5:56 pm

On my Mac it does not to appear in Safari, but it does appear in Firefox.
a // Jan 25, 2009 at 9:24 am

Same problems, using Vista IE. Doesn’t appear to be working
Amy // Feb 5, 2009 at 10:39 pm

what is 1.142 x 10-6 mm2 /8.5 x 10-4 mm +=
David Bradley // Feb 6, 2009 at 8:45 am

Amy, can I ask why you cannot so that on a calculator? What is += meant to mean? You’re dividing square mm by mm, what are you trying to determine?