You need a third-party library for that task. You are using iconv-lite so you need to follow these steps:

1. Open input file in binary mode, so JavaScript doesn't assume UTF-8 nor try to convert to its internal encoding:

   
   
   

   var fs = require(fs);
   
   var input = fs.readFileSync(inputFilePath, {encoding: binary});
   
   




2. Convert from ISO-8859-1 to Buffer:

   
   
   

   var iconv = require('iconv-lite');
   
   var output = iconv.decode(input, ISO-8859-1);
   
   




3. Save Buffer to output file:

   
   
   

   fs.writeFileSync(outputFilePath, output);
   
   

If unsure of encoding names, you can test whether a given encoding is supported with encodingExists():

> iconv.encodingExists(ISO-8859-1);

true