Frequently Asked Questions

Great question! LangDex is sustained through a freemium model. Exploring the database and using basic features is free forever. However, API access for developers and advanced features require a paid subscription. This revenue directly supports ongoing development, server costs, and data maintenance. I'm committed to this project for the long term.

LangDex is built by a single developer with a deep passion for linguistics and language learning. I've been studying multiple languages for years and was frustrated by the fragmented state of linguistic data. I built LangDex to solve my own problems first, and I use it daily for my own language studies. This isn't a venture-backed startup chasing growth metrics; it's a labor of love that I plan to maintain and improve for years to come.

The website and basic dictionary features are free to use. For developers who want API access, we offer tiered pricing starting with a free tier (1,000 requests/day) and paid plans for higher usage. This ensures the project remains sustainable while keeping core features accessible to everyone.

LangDex aggregates data from the best open linguistic datasets available: PanLex for cross-lingual translations, Glottolog for language metadata, Wiktionary (via Kaikki) for dictionary entries, JMDict for Japanese, UniMorph for morphology, Tatoeba for example sentences, and many more. All sources are properly attributed and we respect their licenses.

LangDex covers 5,700+ languages, from major world languages to endangered dialects. Coverage depth varies: well-documented languages like Japanese, Spanish, or German have millions of entries with pronunciation, etymology, and examples. Less-resourced languages may have basic vocabulary linked through PanLex's concept network.

Join the waitlist to be notified when API access becomes available. We're currently in development and will open API access to waitlist members first. The API will offer three 'lenses' (Learn, Analyze, and Research) tailored to different use cases.

We're planning an offline SDK that lets you download compressed language packs for local use. This is especially important for language learning apps that need to work without connectivity. Join the waitlist to be notified when this becomes available.

We welcome feedback! If you find errors in the data, you can report them through the feedback form (coming soon). Since our data comes from open sources, corrections often need to be made upstream. We also plan to add community contribution features in the future.