diyAudio (https://www.diyaudio.com/forums/index.php)
-   Everything Else (https://www.diyaudio.com/forums/everything-else/)
-   -   Convert mm to inches - easy to remember!! (https://www.diyaudio.com/forums/everything-else/340288-convert-mm-inches-easy-remember.html)

 takitaj 15th July 2019 05:42 PM

Convert mm to inches - easy to remember!!

Back in my engineering days I learned an easy and accurate enough way to convert from millimeters or centimeters to inches and back. I thought I would share it with the forums. Some may already know but for those that don't it's one easy number to remember.

The magic number is 0.03937
(actual number is 0.03937007874)

Convert millimeters to inches, multiply -> mm x 0.03937 = inches
Convert inches to millimeters, divide -> inches / 0.03937 = mm

To convert to or from centimeters simply
move it over one decimal place -> cm x 0.3937 = inches

and of course the inverse is the same -> inches / 0.3937 = cm

Have fun!

TJ

 leadbelly 15th July 2019 05:47 PM

Er, thanks?

 Galu 15th July 2019 05:54 PM

Quote:
 Originally Posted by takitaj (https://www.diyaudio.com/forums/everything-else/340288-convert-mm-inches-easy-remember-post5852925.html#post5852925) . . .it's one easy number to remember. The magic number is 0.03937
Thanks, but at my age I'm struggling to remember my PIN numbers! :)

 hudelson2 15th July 2019 06:04 PM

An exact formula to convert millimeters to inches is to divide by 25.4.
There are exactly 25.4 millimeters to an inch.

Instead of working in inches, why not simply buy a tape measure with metric units? You can buy them at Amazon.

John

 scottjoplin 15th July 2019 06:19 PM

Quote:
 Originally Posted by takitaj (https://www.diyaudio.com/forums/everything-else/340288-convert-mm-inches-easy-remember-post5852925.html#post5852925) The magic number is 0.03937
No it's not, it's 0.03937007874

 analog_sa 15th July 2019 06:23 PM

Quote:
 Originally Posted by takitaj (https://www.diyaudio.com/forums/everything-else/340288-convert-mm-inches-easy-remember-post5852925.html#post5852925) Have fun!

Wow! You won't believe the fun i am having. Cannot stop myself converting.

 takitaj 15th July 2019 06:24 PM

I have the means to measure both, thank you. Just thought I'd share for others that might be interested. As you know, in the USA we generally still use inches.

For me, 0.03937 (actual number is 0.03937007874) stuck better than 25.4, for whatever reason. We're all wired differently.

I put it out there, do with it as you wish. :)

TJ

 scottjoplin 15th July 2019 06:28 PM

Not meaning to be pedantic (of course I am) but you said easy and accurate.......... ;)

 takitaj 15th July 2019 06:40 PM

Accurate enough for anything anyone here would use it for! What's 0.00000007874 inches between friends? :D :cheers:

TJ

 badman 15th July 2019 07:23 PM

Quote:
 Originally Posted by takitaj (https://www.diyaudio.com/forums/everything-else/340288-convert-mm-inches-easy-remember-post5852973.html#post5852973) Accurate enough for anything anyone here would use it for! What's 0.00000007874 inches between friends? :D :cheers: TJ
All she'll get, in some bedrooms.

All times are GMT. The time now is 02:35 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.