Without 3rd party extensions! What you need are the fs, readline and stream module. var fs = require('fs'), readline = require('readline'), stream = require('stream'); var instream = fs.createReadStream('your/file'), outstream = new stream, rl = readline.createInterface(instream, outstream); rl.on('line', function(line) { // process line here }); rl.on('close', function(…