NoaLingua Answer
NoaLingua reads its dictionary from your disk
Download once, then look up with no network at all
Dictionary, grammar tables, definitions and example sentences download once and are then read from disk. After that, looking up a word needs no network at all. Expect fifteen to thirty minutes before everything is instant and offline.
Short answer Yes — after a one-time download that is large and worth knowing about before you start.
The detail behind the NoaLingua answer
The download is real, and the sizes are published
Local-first means downloading first. The English dictionary pack is 475 MB, Chinese 145 MB, German 91 MB. Expect fifteen to thirty minutes before everything is instant and offline.
That is a genuine cost and it is stated before you install rather than discovered on the first evening. The packs start downloading by themselves as soon as the extension knows which two languages you picked.
Four languages have no dictionary at all
Serbian, Croatian, Vietnamese and Thai have no dictionary pack, because no Wiktionary extract exists for them. Subtitles, saving and review all work in those languages; the meaning of a word does not appear.
The coverage matrix says this cell by cell, and marks separately the cells we have not verified ourselves — which is not the same as a no.
More questions people ask NoaLingua
Does translation work offline too?
When Chrome has an on-device model for your language pair, yes. Where it does not, translation needs the network even though the dictionary does not.
What happens if the local database is damaged?
There is a repair action for the "internal error opening database" case. It rebuilds the database and keeps your settings, but the cards and downloaded packs are gone — so export your profile first if you can.
Can I use it before the download finishes?
Yes. Dual subtitles work straight away. The part that waits is the word card, because that is what depends on the packs.
Where this is documented on NoaLingua
Related NoaLingua answers
Try it on the next thing you were going to watch anyway.
Free, with every feature. No account, nothing to cancel, and your deck stays on your machine.
Add to Chrome — Free Add to Chrome Opens the Chrome Web Store listing NoaLingua — beyond dual subs: video, web, PDF — free, no account, Chrome 138 or newer.- Free, and not a trial Every feature on the free plan — both PDF modes, shadowing, all 30 practice formats.
- No account, no email Nothing to sign up for and nothing to cancel. There is no login screen at all.
- Two dropdowns to set up Pick what you are learning and what you want translations in. That is the whole setup.
- Your words stay yours Export to Anki, CSV, a spreadsheet or a full JSON profile — free on every plan.