• This would be a better place for the mm label.
  • This would be a perfect place for a cm label.


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Ruler … Why mark mm (millimeters - which aren't numbered) and not the cm (centimeters - which are numbered)? Labeling the 1 as 1 cm would help a student understand that the mm refers to the smallest markings while the numbers refer to the largest markings. See neighboring photos. Especially this one. Why manufacturers seem to be STUPID, INCOMPETENT, or both.

I originally took the picture as part of a worksheet to help my students distinguish between imperial and metric measurement. Many tended to get confused, thinking the mm indicates that the numbers are millimeters. So now I look at such loose labeling as a symbol of the incompetence of ruler manufacturers. Usually these same rulers mark the other side as "inches" and the inches are numbered. So why do they mark the metric side "mm" when they number the centimeters??!!

I'd rather they put cm after the number 1, and shrink the mm and nestle it down next to the mm markings, between zero and 5mm. The way they have it is just too ambiguous, especially for people who struggle with the metric system.

For the life of me, I cannot figure out why this picture has more than a couple of views. I put it up more as a joke. If you feel like it, let me know why you are looking at it.

vishucreation, Stephan.Kassel, and 12 other people added this photo to their favorites.

  1. rpdexter 82 months ago | reply

    Lol! I looked at this picture b/c I lost my ruler and had to measure something. Therefore, I looked up rulers and this pic came up. This particular picture won't help me b/c it's too big & and it's not the whole thing.

  2. Lucy Jaffe 79 months ago | reply

    We'd like to use your picture, is that OK?

  3. warty2200 72 months ago | reply

    I came to this pic by looking for pics of Lake Powell. You had a great shot of the lake from a plane heading west. Then I noticed your user name. I love the Islands so I looked around. Found this ruler pic and tried to figure what's wrong with it. Your'e right; it should be marked "cm".

  4. allendesarae 64 months ago | reply

    I was trying to get an accurate measurement regarding the toy I just bought.


  5. tiny club rock show 57 months ago | reply

    I came by because I'm looking for a photo of a ruler for an art project I'm doing.

  6. lapremera2 42 months ago | reply

    have no comet

  7. m.renshaw23 42 months ago | reply

    I wanted an image to demonstrate the idea of 'reliability' to a group of students on a research course, and threats to that reliability. So a ruler that we might assume was measured out in inches but had no clear indication that this was the case, seemed a good way to start discussing the subject!

  8. glaukos 35 months ago | reply

    I was looking for a place to buy the rulers seen in scientific field photos, e.g. indicating size of animal tracks or plants. They have very bold markings including alternating blocks of black and white to make it clear what size the object is.

    But I’m commenting because I can contribute another “incompetent manufacturers“ story. My husband is a textile artist and at one point his work was not coming out quite square. He found out at last that two metal yeardsticks he had bought---not cheap either--- were 1/4 inch wrong. Made in Korea.

  9. sagarraste 32 months ago | reply

    Great Shot!!!

  10. richardmaun 25 months ago | reply

    i borrowed your super pic for my blog, credited to you. Thanks!

  11. Kiffer the Original 23 months ago | reply

    I was looking for something completely different and this came up. I looked because I wanted to know who and why would somebody post a picture of the end of a ruler.

  12. Different Apple 13 months ago | reply

    I was looking at your photostream because you had commented on mine. I was confused by the set title 5000+ views and wondered why 5000 people would want to look at a close up of a ruler. Lol

  13. Biking Nikon SFO 6 weeks ago | reply

    Thank you all for your comments!
