POEditor

This plugin will let you manage your POEditor translations directly from WordPress via the POEditor API.
It will fetch all your projects from POEditor.com, based on your API KEY, and it will scan your /wp-content/ folder for gettext language files (.po and .pot). After this, you can assign files from your WordPress themes or plugins to your POEditor language files and you can import, export or sync your files with the POEditor translations.
You can find step by step instructions on how to use the POEditor plugin in this <a href="http://blog.poeditor.com/how-to-translate-wordpress-themes-and-plugins-using-the-poeditor-localization-plugin/" rel="nofollow ugc">localization guide</a>.
If you want to contribute to the localization of this plugin, please go to the <a href="https://poeditor.com/join/project/90c87a6885fac137e7810f31a1a5296f" rel="nofollow ugc">plugin’s translation page</a> and join the translation effort.
You can also contribute to plugin’s development on <a href="https://github.com/POEditor/poeditor_wp_plugin" rel="nofollow ugc">GitHub</a>.

This plugin will let you manage your POEditor translations directly from Wordpress via the POEditor API.

guelben

This plugin allow you to translate your monolingual website in a super easy manner. You do not have to bother about .pot .po or .mo files. It safes you a lot of time cause you can effectively transalte thouse texts in a foreign language with just a few clicks gaining productivity. Bravo translate keeps your translations in your database. You dont have to worry about themes or plugins updates because your translations will not vannish.
<h3>Some texts are not translated how can I fix it?</h3>
If some of your texts are not translated, inspect your source code and check how they are written in your html. Sometimes the text is altered by css uppercasing. Other times some html tags may be inside your texts. Do not hesitate to copy thouse html tags.
For instance lets suppose you have this in your source code :
This is my super title
The translation of the text “This is my super title” will not work. Instead, copy “This is my super title” and insert it at the Text to Translate field.
<h3>Does this plugin slows my site?</h3>
This plugin has a very low impact in your page loading time. However try to limit very shorts texts to translate ( text with only 2 or 3 characters long). The plugin will find a lot of ocurrences of thouse short texts and it will have a lot of job to do deciding if it is text to translate or not. 
If you put a lot of texts with just 2 characters, you may increase the loading time by a some millisecs (of course that will also depend on your server performance).

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