Currency Rates Library

January 26, 2011

The Rub

I needed a way of grabbing up to date currency information and an easy way to convert currencies using these up to date rates.

Normally this information requires signing up for premium accounts or writing web scrapers to do this for you.

It turns out that the European bank provides a daily xml for free that contains this information. It is specific to the euro but is fairly trivial to convert this into conversion rates for any of the other currency as the base currency.

Currency Rates is born

gem install currency_rates

It is a simple class for getting up to date currency rates in an array. You pass a base currency which the rates will be calculated against. Connects to the european bank to get a daily breakdown of the rates.

Deliberately lightweight to allow you to build on top of.


#!/usr/bin/env ruby

require 'rubygems'
require 'currency_rates'

parser ='GBP')
puts parser.engage.inspect

Valid values for the initialize call are:


Example result array:

[{"currency"=>"USD", "rate"=>"1.58482"}, {"currency"=>"JPY", "rate"=>"130.28671"}, {"currency"=>"BGN", "rate"=>"2.26562"}, {"currency"=>"CZK", "rate"=>"28.05560"}, {"currency"=>"DKK", "rate"=>"8.63284"}, {"currency"=>"ILS", "rate"=>"5.71573"}, {"currency"=>"GBP", "rate"=>"1.00000"}, {"currency"=>"HUF", "rate"=>"317.67159"}, {"currency"=>"LTL", "rate"=>"3.99977"}, {"currency"=>"LVL", "rate"=>"0.81552"}, {"currency"=>"PLN", "rate"=>"4.48653"}, {"currency"=>"RON", "rate"=>"4.94642"}, {"currency"=>"SEK", "rate"=>"10.26180"}, {"currency"=>"CHF", "rate"=>"1.49690"}, {"currency"=>"NOK", "rate"=>"9.11266"}, {"currency"=>"HRK", "rate"=>"8.58558"}, {"currency"=>"RUB", "rate"=>"47.14741"}, {"currency"=>"TRY", "rate"=>"2.50090"}, {"currency"=>"AUD", "rate"=>"1.58992"}, {"currency"=>"BRL", "rate"=>"2.64361"}, {"currency"=>"CAD", "rate"=>"1.57892"}, {"currency"=>"CNY", "rate"=>"10.43290"}, {"currency"=>"HKD", "rate"=>"12.33837"}, {"currency"=>"IDR", "rate"=>"14323.90385"}, {"currency"=>"INR", "rate"=>"72.43649"}, {"currency"=>"KRW", "rate"=>"1770.37938"}, {"currency"=>"MXN", "rate"=>"19.10177"}, {"currency"=>"MYR", "rate"=>"4.83614"}, {"currency"=>"NZD", "rate"=>"2.06591"}, {"currency"=>"PHP", "rate"=>"70.20678"}, {"currency"=>"SGD", "rate"=>"2.02989"}, {"currency"=>"THB", "rate"=>"48.82247"}, {"currency"=>"ZAR", "rate"=>"11.25607"}, {"currency"=>"EUR", "rate"=>"1.15841"}]

Code is also available on github