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i18n-express v1.1.3

A simple i18n middleware for Express.js.


Build Status npm version

A simple i18n middleware for Express.js This module just reads all the .json files in a directory. Then calculates the user lang and exposes "texts" variables in your views with the texts in that json.

By default, the user will see the site in the language set by the cookieLangName session. If the session is not set, the language set by the browser will be used.

If the user wants to set the language to spanish for example, he would have to visit (clang is defined at paramLangName).

This can be done by using a html 'select' or any other means you want. Once that is done, the cookieLangName session will be updated with the new language and the user will forever see the site in the new language until he decides to set a new language again.

NOTE: When using this module, we recommend also using the geolang-express module, which sets the cookieLangName session to a language based on the visit IP address.


  • Node >= 0.12
  • Express.js


$ npm install i18n-express


var i18n=require("i18n-express");

app.use( i18n(options) );


  • translationsPath : (default: i18n) The path where you store translations json files.
  • cookieLangName : (default: ulang) If you provide a cookie name, try to get user lang from this cookie.
  • browserEnable : (default: true) If enabled, try to get user lang from browser headers.
  • defaultLang : (default: en) If all others methods fail, use this lang.
  • paramLangName : (default: clang) Get param to change user lang. ej: visiting '' the lang switchs to 'es'
  • siteLangs : (default: ['en']) Array of supported langs. (posbile values for clang and json files)
  • textsVarName : (default: texts) Name of variable which holds the loaded translations.


Create a directory "i18n" with .json files for each lang. Ej:

  • en.json
  • es.json
  • en-us.json

With translations like this (en.json):

"WELCOME_MSG": "Hi! Welcome!",
"CONTACT_TEXT": "More bla"

In your Express app.js:

var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var i18n=require("i18n-express"); // <-- require the module

var indexRoutes = require('./routes/index');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
app.use(express.static(path.join(__dirname, 'public')));
  secret: 'secret',
  saveUninitialized: true,
  resave: true

  translationsPath: path.join(__dirname, 'i18n'), // <--- use here. Specify translations files path.
  siteLangs: ["en","es"],
  textsVarName: 'translation'

app.use('/', indexRoutes);

module.exports = app;


Now in your ejs view you have texts object and lang variable with the active language:

  Choose your language:
    <li><a class="<%=(lang=="es"?"active":"")%>" href="/?clang=es">Spanish</a></li>
    <li><a class="<%=(lang=="en"?"active":"")%>" href="/?clang=en">English</a></li>


Or in your handlebars view:

  Choose your language:
    <li><a href="/?clang=es">Spanish</a></li>
    <li><a href="/?clang=en">English</a></li>






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