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A scientific conversion library.
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Build Status Code Climate

Doing conversions for you so you don’t have to google them and making code more readable.

Having code that looks like this is meaningless

meters = 8 * 1609.344

You could add comments

meters = 8 * 1609.344 # converting miles to meters

But why not have this!

You can even perform mathematical operations

10.kilometers + 1.mile # 11.609344 kilometers

Handling bytes now works according to the JEDEC memory standard == 1024.0

Converting distance of arc length on Earth to an (approximate) corresponding spherical geometry angle can be done with

require 'alchemist/geospatial' == 0.014457066992474555

To switch to the IEC memory standard, force SI units with

Alchemist::use_si = true

To see all the units alchemist has built in conversion for, check out the units file

You may also register your own units

Alchemist.register(:distance, [:beard_second, :beard_seconds], 5.angstroms)


gem install alchemist


In order for methods like 1.meter to work, you'll either need to setup Alchemist yourself:

Alchemist.setup # This will load every category of measurement

if you only want to use one category for conversions you can load it individually:

Alchemist.setup('distance') # This will load only distance



It is suggested that you add your Alchemist.setup call to config/initializers/alchemist.rb and then restart your rails server.

Rails Warning

Rails adds some methods like bytes to Numeric so it's highly recommended that instead of trying to call bytes on a numeric, you should use the measure method:

Alchemist.measure(10, :bytes)


Alchemist is licensed under the MIT license as specified in the gemspec

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