diff --git a/addons/http_routing/models/ir_http.py b/addons/http_routing/models/ir_http.py
index 0da7d82e1e2..d6a4524eb31 100644
--- a/addons/http_routing/models/ir_http.py
+++ b/addons/http_routing/models/ir_http.py
@@ -246,6 +246,7 @@ class IrHttp(models.AbstractModel):
             'lang_parameters': lang_params,
             'modules': translations,
             'multi_lang': len(request.env['res.lang'].sudo().get_installed()) > 1,
+            'lang': lang,
         }
 
         session_info.update({
diff --git a/addons/web/controllers/main.py b/addons/web/controllers/main.py
index 1487fbdeba9..10e350fbd0a 100644
--- a/addons/web/controllers/main.py
+++ b/addons/web/controllers/main.py
@@ -793,6 +793,7 @@ class WebClient(http.Controller):
         translations_per_module, lang_params = request.env["ir.translation"].get_translations_for_webclient(mods, lang)
 
         body = json.dumps({
+            'lang': lang,
             'lang_parameters': lang_params,
             'modules': translations_per_module,
             'multi_lang': len(request.env['res.lang'].sudo().get_installed()) > 1,
diff --git a/addons/web/models/ir_http.py b/addons/web/models/ir_http.py
index 5d1ac1aac11..f5a9f922abf 100644
--- a/addons/web/models/ir_http.py
+++ b/addons/web/models/ir_http.py
@@ -33,6 +33,7 @@ class Http(models.AbstractModel):
         lang = user_context.get("lang")
         translations_per_module, lang_params = request.env['ir.translation'].get_translations_for_webclient(mods, lang)
         translation_cache = {
+            'lang': lang,
             'lang_parameters': lang_params,
             'modules': translations_per_module,
             'multi_lang': len(request.env['res.lang'].sudo().get_installed()) > 1,
diff --git a/addons/web/static/src/js/core/translation.js b/addons/web/static/src/js/core/translation.js
index 416ea9130d2..5335f4716a7 100644
--- a/addons/web/static/src/js/core/translation.js
+++ b/addons/web/static/src/js/core/translation.js
@@ -13,7 +13,8 @@ var TranslationDataBase = Class.extend(/** @lends instance.TranslationDataBase#
                         "time_format": '%H:%M:%S',
                         "grouping": [],
                         "decimal_point": ".",
-                        "thousands_sep": ","};
+                        "thousands_sep": ",",
+                        "code": "en_US"};
     },
     set_bundle: function(translation_bundle) {
         var self = this;
diff --git a/addons/web/static/src/js/fields/basic_fields.js b/addons/web/static/src/js/fields/basic_fields.js
index dbafc45e592..d226ef655c7 100644
--- a/addons/web/static/src/js/fields/basic_fields.js
+++ b/addons/web/static/src/js/fields/basic_fields.js
@@ -41,9 +41,11 @@ var TranslatableFieldMixin = {
      */
     _renderTranslateButton: function () {
         if (_t.database.multi_lang && this.field.translate && this.res_id) {
+            var lang = _t.database.parameters.code.split('_')[0].toUpperCase();
             return $('<button>', {
                     type: 'button',
                     'class': 'o_field_translate fa fa-globe btn btn-link',
+                    'data-code': lang,
                 })
                 .on('click', this._onTranslate.bind(this));
         }
diff --git a/addons/web/static/src/scss/form_view.scss b/addons/web/static/src/scss/form_view.scss
index 51920df3510..f01fedbbab1 100644
--- a/addons/web/static/src/scss/form_view.scss
+++ b/addons/web/static/src/scss/form_view.scss
@@ -578,10 +578,11 @@
     .o_field_translate {
         padding: 0;
         cursor: pointer;
-        width: 12px !important;
+        width: 35px !important;
         vertical-align: top;
         &::before { // seems to be useful for some old browser
             position: relative;
+            content: attr(data-code);
         }
     }
 
diff --git a/addons/web/static/src/scss/form_view_extra.scss b/addons/web/static/src/scss/form_view_extra.scss
index 49d14438e33..77b713784fe 100644
--- a/addons/web/static/src/scss/form_view_extra.scss
+++ b/addons/web/static/src/scss/form_view_extra.scss
@@ -82,7 +82,7 @@
 
     // Translate icon
     .o_field_translate {
-        margin-left: -15px;
+        margin-left: -35px;
     }
 
     // Specific style classes
diff --git a/odoo/addons/base/models/ir_translation.py b/odoo/addons/base/models/ir_translation.py
index c5f6f7878b9..f553c847205 100644
--- a/odoo/addons/base/models/ir_translation.py
+++ b/odoo/addons/base/models/ir_translation.py
@@ -833,6 +833,7 @@ class IrTranslation(models.Model):
                 "name", "direction", "date_format", "time_format",
                 "grouping", "decimal_point", "thousands_sep", "week_start"])[0]
             lang_params['week_start'] = int(lang_params['week_start'])
+            lang_params['code'] = lang
 
         # Regional languages (ll_CC) must inherit/override their parent lang (ll), but this is
         # done server-side when the language is loaded, so we only need to load the user's lang.