diff --git a/data/locales.json b/data/locales.json
index 44287a1d9..1e5fde723 100644
--- a/data/locales.json
+++ b/data/locales.json
@@ -1,66 +1,190 @@
 {
-    "dataLocales": [
-        "af",
-        "sq",
-        "ar",
-        "ar-AA",
-        "hy",
-        "ast",
-        "bn",
-        "bs",
-        "bg-BG",
-        "ca",
-        "zh",
-        "zh-CN",
-        "zh-HK",
-        "zh-TW",
-        "yue",
-        "hr",
-        "cs",
-        "da",
-        "nl",
-        "en-GB",
-        "eo",
-        "et",
-        "fi",
-        "fr",
-        "gl",
-        "de",
-        "el",
-        "gu",
-        "hi",
-        "hu",
-        "is",
-        "id",
-        "it",
-        "ja",
-        "kn",
-        "ko",
-        "ku",
-        "lv",
-        "lij",
-        "lt",
-        "ml",
-        "no",
-        "fa",
-        "pl",
-        "pt",
-        "pt-BR",
-        "ro",
-        "ru",
-        "sc",
-        "sr",
-        "si",
-        "sk",
-        "sl",
-        "es",
-        "sv",
-        "tl",
-        "ta",
-        "te",
-        "th",
-        "tr",
-        "uk",
-        "vi"
-    ]
+    "dataLocales": {
+        "af": {
+            "rtl": false
+        },
+        "ar": {
+            "rtl": true
+        },
+        "ar-AA": {
+            "rtl": true
+        },
+        "ast": {
+            "rtl": false
+        },
+        "bg-BG": {
+            "rtl": false
+        },
+        "bn": {
+            "rtl": false
+        },
+        "bs": {
+            "rtl": false
+        },
+        "ca": {
+            "rtl": false
+        },
+        "cs": {
+            "rtl": false
+        },
+        "da": {
+            "rtl": false
+        },
+        "de": {
+            "rtl": false
+        },
+        "el": {
+            "rtl": false
+        },
+        "en-GB": {
+            "rtl": false
+        },
+        "eo": {
+            "rtl": false
+        },
+        "es": {
+            "rtl": false
+        },
+        "et": {
+            "rtl": false
+        },
+        "fa": {
+            "rtl": true
+        },
+        "fi": {
+            "rtl": false
+        },
+        "fr": {
+            "rtl": false
+        },
+        "gl": {
+            "rtl": false
+        },
+        "gu": {
+            "rtl": false
+        },
+        "hi": {
+            "rtl": false
+        },
+        "hr": {
+            "rtl": false
+        },
+        "hu": {
+            "rtl": false
+        },
+        "hy": {
+            "rtl": false
+        },
+        "id": {
+            "rtl": false
+        },
+        "is": {
+            "rtl": false
+        },
+        "it": {
+            "rtl": false
+        },
+        "ja": {
+            "rtl": false
+        },
+        "kn": {
+            "rtl": false
+        },
+        "ko": {
+            "rtl": false
+        },
+        "ku": {
+            "rtl": false
+        },
+        "lij": {
+            "rtl": false
+        },
+        "lt": {
+            "rtl": false
+        },
+        "lv": {
+            "rtl": false
+        },
+        "ml": {
+            "rtl": false
+        },
+        "nl": {
+            "rtl": false
+        },
+        "no": {
+            "rtl": false
+        },
+        "pl": {
+            "rtl": false
+        },
+        "pt": {
+            "rtl": false
+        },
+        "pt-BR": {
+            "rtl": false
+        },
+        "ro": {
+            "rtl": false
+        },
+        "ru": {
+            "rtl": false
+        },
+        "sc": {
+            "rtl": false
+        },
+        "si": {
+            "rtl": false
+        },
+        "sk": {
+            "rtl": false
+        },
+        "sl": {
+            "rtl": false
+        },
+        "sq": {
+            "rtl": false
+        },
+        "sr": {
+            "rtl": false
+        },
+        "sv": {
+            "rtl": false
+        },
+        "ta": {
+            "rtl": false
+        },
+        "te": {
+            "rtl": false
+        },
+        "th": {
+            "rtl": false
+        },
+        "tl": {
+            "rtl": false
+        },
+        "tr": {
+            "rtl": false
+        },
+        "uk": {
+            "rtl": false
+        },
+        "vi": {
+            "rtl": false
+        },
+        "yue": {
+            "rtl": false
+        },
+        "zh": {
+            "rtl": false
+        },
+        "zh-CN": {
+            "rtl": false
+        },
+        "zh-HK": {
+            "rtl": false
+        },
+        "zh-TW": {
+            "rtl": false
+        }
+    }
 }
\ No newline at end of file
diff --git a/data/update_locales.js b/data/update_locales.js
index 9dd554698..7be9af8a0 100644
--- a/data/update_locales.js
+++ b/data/update_locales.js
@@ -1,8 +1,9 @@
 /* Downloads the latest translations from Transifex */
 
-var request = require('request').defaults({maxSockets: 1}),
+var request = require('request').defaults({ maxSockets: 1 }),
     yaml = require('js-yaml'),
     fs = require('fs'),
+    stringify = require('json-stable-stringify'),
     _ = require('lodash');
 
 var resources = ['core', 'presets'];
@@ -26,27 +27,39 @@ var auth = JSON.parse(fs.readFileSync('./transifex.auth', 'utf8'));
 var sourceCore = yaml.load(fs.readFileSync('./data/core.yaml', 'utf8')),
     sourcePresets = yaml.load(fs.readFileSync('./data/presets.yaml', 'utf8'));
 
+
 asyncMap(resources, getResource, function(err, locales) {
     if (err) return console.log(err);
 
     var locale = _.merge(sourceCore, sourcePresets),
-        codes = [];
+        dataLocales = {};
 
     locales.forEach(function(l) {
         locale = _.merge(locale, l);
     });
 
-    for (var i in locale) {
-        if (i === 'en' || _.isEmpty(locale[i])) continue;
-        codes.push(i);
-        var obj = {};
-        obj[i] = locale[i];
-        fs.writeFileSync(outdir + i + '.json', JSON.stringify(obj, null, 4));
-    }
-
-    fs.writeFileSync('data/locales.json', JSON.stringify({ dataLocales: codes }, null, 4));
+    asyncMap(Object.keys(locale),
+        function(code, done) {
+            if (code === 'en' || _.isEmpty(locale[code])) {
+                done();
+            } else {
+                var obj = {};
+                obj[code] = locale[code];
+                fs.writeFileSync(outdir + code + '.json', JSON.stringify(obj, null, 4));
+                getLanguageInfo(code, function(err, info) {
+                    dataLocales[code] = { rtl: info && info.rtl };
+                    done();
+                });
+            }
+        }, function(err) {
+            if (!err) {
+                fs.writeFileSync('data/locales.json', stringify({ dataLocales: dataLocales }, { space: 4 }));
+            }
+        }
+    );
 });
 
+
 function getResource(resource, callback) {
     resource = project + 'resource/' + resource + '/';
     getLanguages(resource, function(err, codes) {
@@ -65,6 +78,7 @@ function getResource(resource, callback) {
     });
 }
 
+
 function getLanguage(resource) {
     return function(code, callback) {
         code = code.replace(/-/g, '_');
@@ -78,6 +92,18 @@ function getLanguage(resource) {
     };
 }
 
+
+function getLanguageInfo(code, callback) {
+    code = code.replace(/-/g, '_');
+    var url = api + 'language/' + code;
+    request.get(url, { auth : auth }, function(err, resp, body) {
+        if (err) return callback(err);
+        console.log(resp.statusCode + ': ' + url);
+        callback(null, JSON.parse(body));
+    });
+}
+
+
 function getLanguages(resource, callback) {
     var url = resource + '?details';
     request.get(url, { auth: auth },
@@ -92,6 +118,7 @@ function getLanguages(resource, callback) {
     });
 }
 
+
 function asyncMap(inputs, func, callback) {
     var remaining = inputs.length,
         results = [],
diff --git a/package.json b/package.json
index 6d3b7f57e..071d9625c 100644
--- a/package.json
+++ b/package.json
@@ -49,6 +49,7 @@
     "happen": "~0.3.1",
     "js-yaml": "~3.7.0",
     "jsonschema": "~1.1.0",
+    "json-stable-stringify": "~1.0.1",
     "maki": "0.5.0",
     "mapillary-js": "2.1.0",
     "minimist": "~1.2.0",