Inventory of dictionaries shipping in Firefox Desktop

41 locales have an in-tree dictionary

Code Language Dictionary Version Status Last check License Source Nightly-only locale
ach Acholi  
af Afrikaans  
an Aragonese  
ar Arabic Yes 3.7 2025: Added Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 github.com  
ast Asturian 4.4.5 Incompatible license Apr 2026 GPL-3.0 addons.mozilla.org  
az Azerbaijani  
be Belarusian  
bg Bulgarian Yes 4.4.5 2026: Updated Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 sourceforge.net  
bn Bengali  
bo Tibetan Yes 0.4.0 2026: Added Apr 2026 CC0 github.com Nightly-only locale
br Breton Yes 0.14 Up to date Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 drouizig.org  
brx Bodo Nightly-only locale
bs Bosnian  
ca Catalan Yes 3.0.9 2025: Updated Apr 2026 GPL-2.0 / LGPL-2.1 github.com  
ca-valencia Catalan (Valencian) Yes 3.0.9 2025: Added Apr 2026 GPL-2.0 / LGPL-2.1 github.com  
cak Kaqchikel  
ckb Central Kurdish Nightly-only locale
cs Czech  
cy Welsh Yes 25.03 2026: Added Apr 2026 LGPL-3.0 github.com  
da Danish Yes 2.9.097 2026: Updated Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 stavekontrolden.dk  
de German  
dsb Lower Sorbian  
el Greek Yes 0.9 2025: Updated Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 addons.mozilla.org  
en-CA English (Canada) Yes 2020.12.07 Up to date Apr 2026 BSD wordlist.aspell.net  
en-GB English (UK)  
eo Esperanto  
es-AR Spanish (Argentina) Yes 2.9 2025: Updated Apr 2026 GPL-3.0 / LGPL-3.0 / MPL-1.1 github.com  
es-CL Spanish (Chile) Yes 2.9 2025: Updated Apr 2026 GPL-3.0 / LGPL-3.0 / MPL-1.1 github.com  
es-ES Spanish (Spain) Yes 2.9 2025: Updated Apr 2026 GPL-3.0 / LGPL-3.0 / MPL-1.1 github.com  
es-MX Spanish (Mexico) Yes 2.9 2025: Updated Apr 2026 GPL-3.0 / LGPL-3.0 / MPL-1.1 github.com  
et Estonian Yes 1.0 Up to date Apr 2026 LGPL-2.1 extensions.services.openoffice.org  
eu Basque  
fa Persian Yes 3.3 2026: Added Apr 2026 Apache-2.0 github.com  
ff Fulah  
fi Finnish 0.2 2026: Candidate Apr 2026 CC0 github.com  
fr French Yes 7.7 2026: Updated Apr 2026 MPL-2.0 grammalecte.net  
fur Friulian  
fy-NL Frisian Yes 20160722 2025: Updated Apr 2026 Apache 2.0 www.fryslan.frl  
ga-IE Irish  
gd Scottish Gaelic  
gl Galician  
gn Guarani  
gu-IN Gujarati  
he Hebrew  
hi-IN Hindi  
hr Croatian  
hsb Upper Sorbian  
hu Hungarian Yes 1.9 2026: Updated Apr 2026 MPL-2.0 / LGPL-3.0 github.com  
hy-AM Armenian  
hye Easter Armenian Nightly-only locale
ia Interlingua  
id Indonesian Yes 2.3.0 2026: Updated Apr 2026 MPL-2.0 / LGPL-3.0 github.com  
is Icelandic  
it Italian  
ja Japanese Yes 2020.12.07 Up to date Apr 2026 BSD wordlist.aspell.net  
ja-JP-mac Japanese (mac) Yes 2020.12.07 Up to date Apr 2026 BSD wordlist.aspell.net  
ka Georgian Yes 0.1 2026: Added Apr 2026 MIT github.com  
kab Kabyle  
kk Kazakh  
km Khmer  
kn Kannada  
ko Korean Incompatible license Apr 2026 GPL-3.0 github.com  
ku Kurdish 0.96 Unknown source Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 addons.mozilla.org Nightly-only locale
lij Ligurian  
lo Lao Nightly-only locale
lt Lithuanian Yes 1.3.2 Up to date Apr 2026 BSD github.com  
ltg Latgalian Nightly-only locale
lv Latvian Yes 1.5.0 2026: Updated Apr 2026 LGPL-2.1 dict.dv.lv  
meh Southwestern Tlaxiaco Mixtec Nightly-only locale
mk Macedonian 2025: Removed May 2025 wiki.mozilla.org  
ml Malayalam Nightly-only locale
mr Marathi  
ms Malay  
my Burmese  
nb-NO Norwegian Bokmål  
ne-NP Nepali  
nl Dutch Yes 2.20.19 Up to date Apr 2026 BSD github.com  
nn-NO Norwegian Nynorsk  
oc Occitan  
pa-IN Punjabi  
pl Polish Yes 2026-05-11 2026: Updated Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 sjp.pl  
pt-BR Portuguese (Brasil) Yes 140.2025.142.1267 2025: Updated Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 addons.mozilla.org  
pt-PT Portuguese Yes 20.10.5.1 Up to date Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1  
rm Romantch Yes 1.0 Up to date Apr 2026 MIT  
ro Romanian Yes 3.3.10 Up to date Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 sourceforge.net  
ru Russian Yes 1.2 2026: Outdated May 2025 Custom, see source bugzilla.mozilla.org  
sat Santali  
sc Sardinian  
scn Sicilian Nightly-only locale
sco Scots  
si Sinhala  
sk Slovak Yes 2.03-0, 2009-12-05 Up to date Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1 spell.linux.sk  
skr Saraiki  
sl Slovenian Yes 2025.01.02 2026: Added Apr 2026 GPL-2.0 / LGPL-2.1 spell.linux.sk  
son Songhay  
sq Albanian  
sr Serbian Yes 2010-08-18 Unknown source Apr 2026 GPL-2.0 / LGPL-2.1 / MPL-1.1  
sv-SE Swedish Yes 1.21 2026: Outdated Apr 2026 LGPL-3.0 addons.mozilla.org  
szl Silesian  
ta Tamil  
te Telugu  
tg Tajik Yes 1.0.0 2026: Added Apr 2026 MIT github.com  
th Thai  
tl Tagalog  
tr Turkish Yes 1.1.1 2026: Added Apr 2026 MPL-2.0 addons.mozilla.org  
trs Triqui No dictionary found Apr 2026  
uk Ukrainian Yes 6.8.0 2026: Updated Apr 2026 GPL-3.0 / LGPL-2.1 / MPL-1.1 github.com  
ur Urdu 6.8.0 Incompatible license Apr 2026 Unclear if MPL, GPL or LGPL. addons.mozilla.org  
uz Uzbek Incompatible license Apr 2026 GPL-2.0 addons.mozilla.org  
vi Vietnamese 2024: Removed May 2025  
wo Wolof No dictionary found Apr 2026 Nightly-only locale
xh Xhosa Yes 20110323.3 2026: Added Apr 2026 LGPL-2.1 addons.mozilla.org  
zh-CN Chinese (Simplified) No dictionary found Apr 2026  
zh-TW Chinese (Traditional) Yes 2020.12.07 Up to date Apr 2026 BSD wordlist.aspell.net