# Stupid question: Weighing yourself with 2 scales **URL:** \ **Category:** Factual Questions\ **Created:** [June 21, 2004, 12:06am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374 "2004-06-21T00:06:20Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [June 21, 2004, 12:06am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/1 "2004-06-21T00:06:20Z")
The only scales I can find to purchase only weigh up to around 250 pounds, which I’m over. So I figured I’d buy 2 scales, put one foot on each scale, and add them to get the correct weight. Seems simple, obvious. Only… the people I’ve mentioned it to have all said basically “uh… no… that won’t work. I dunno why, but it won’t.” So, it’s a stupid question, but… is there anything I overlooked? is there some reason that method wouldn’t work? ---
**Author:** ![x-ray\_vision](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/x-ray_vision/32/351_2.png) [@x-ray\_vision](https://boards.straightdope.com/u/x-ray_vision)\ **Post date:** [June 21, 2004, 12:18am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/2 "2004-06-21T00:18:05Z")
It works. ---
**Author:** ![TJdude825](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@TJdude825](https://boards.straightdope.com/u/TJdude825)\ **Post date:** [June 21, 2004, 12:20am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/3 "2004-06-21T00:20:09Z")
The only thing I can think of is if you were to shift more of your weight onto one foot, then the other. At any given moment, the sum of the 2 numbers will be correct, but if you shifted to your right slightly to read the one on the right, then shifted over to your left slightly, without realizing it, you’d get a reading that was too high. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [June 21, 2004, 12:56am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/4 "2004-06-21T00:56:26Z")
We’ve discussed this before: > **[A Scale of Two Fatties](https://boards.straightdope.com/sdmb/showthread.php?t=149655)** > > I was hoping someone could shed some light on this argument: “If a person were to place each of their feet on two separate scales, the sum of the readings would be equal to the weight of that person.” Personally, I think that it is true, but others... > **[standing on a scale](https://boards.straightdope.com/sdmb/showthread.php?t=51293)** > > or rather, two scales. would half of my weight show up on each, or a function of theta (theta being the angle of my splayed legs)? thanks a million, jb ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [June 21, 2004, 1:09am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/5 "2004-06-21T01:09:45Z")
Ah, thanks. It was such a stupid question that I didn’t even consider doing a search for it, I didn’t think there’d be anything. Anyway, that’s a good observation about leaning one way and recording the number - I guess I can just take a picture with a digital camera and get both numbers simultaneously. ---
**Author:** ![I\_Love\_Me\_Vol.I](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/i_love_me_vol.i/32/521_2.png) [@I\_Love\_Me\_Vol.I](https://boards.straightdope.com/u/I_Love_Me_Vol.I)\ **Post date:** [June 21, 2004, 1:12am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/6 "2004-06-21T01:12:26Z")
Golly… lots and lots of folks weigh more than 250 pounds. There must be bathroom scales commercially available that go over 250 pounds. ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [June 21, 2004, 1:17am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/7 "2004-06-21T01:17:01Z")
I’d imagine there are, but of the ones I saw at places like k-mart, there weren’t. I figured picking up 2 cheap 250 pound scales would probably be easier than seeking out a heavier duty scale, but I can keep my eye out. ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [June 21, 2004, 4:02am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/8 "2004-06-21T04:02:59Z")
> [@Crafter\_Man](#): > > We’ve discussed this before: I barely remembered, but I see I put in my two cents. But here’s more: if you’re worried about breaking the scales (that’s sometimes the case), stepping onto one, and then the other, is going to put the first in jeopardy. In that case, put a board over both, then step onto the middle of the board. Don’t forget to subtract the weight of the board. ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [June 21, 2004, 4:58am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/9 "2004-06-21T04:58:33Z")
Well, that’s a good idea, but I wasn’t concerned with breaking them - just that my weight would exceed the range their spring could handle and I wouldn’t be able to get a reading. Looks like I can buy $80 high quality scales off of [amazon.com](http://amazon.com), but it’s easier and cheaper just to go with 2 cheap scales. ---
**Author:** ![flight](https://avatars.discourse-cdn.com/v4/letter/f/bbce88/32.png) [@flight](https://boards.straightdope.com/u/flight)\ **Post date:** [June 21, 2004, 5:07am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/10 "2004-06-21T05:07:02Z")
It just so happens I have two scales right here. The girlfriend just bought a second as the first was somewhat inconsistent. They are both digital. Using one foot on each works fine but you have tobe very still or they give you an error message because your weight is shifting too much. Obviously you will not have this problem if they are mechanical. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 21, 2004, 7:30am UTC](https://boards.straightdope.com/t/stupid-question-weighing-yourself-with-2-scales/251374/11 "2004-06-21T07:30:41Z")
In theory the sum of the two weights should equal the total, but there are a couple of reasons why it might not qork out that way in practice: - If the scales are set apart a little, they may be measuring not only your weight, but an additional sideways component (the load cell in the scale may not be able to tell the difference) - Particularly with digital scales, the weight measurement is ‘sampled’, rather than being continuously measured; if you happen to shift your body a little to the left at the moment when the left scale samples and move to the right when the right scale samples, you could end up with a total weight that is too high. But apart from that, there’s nowhere else for the downward force to go; it _should_ add up to the real total.