/api/convert?input=4gal
/api/convert?input=1/2km
/api/convert?input=5.4/3lbs
/api/convert?input=kg
{
initNum: 3.1,
initUnit: 'mi',
returnNum: 4.98895,
returnUnit: 'km',
string: '3.1 miles converts to 4.98895 kilometers'
}