Credits and licences

Last updated 2026-10-06.

Ladu stands on the work of other people. This page names the data and software we use, and the licences they come with.

Word data

• Dictionary word forms (English, German and Spanish). Derived from English Wiktionary through kaikki.org (Wiktextract), by its contributors. We keep only the word forms the word editor fills. Licence: CC BY-SA 4.0.
• Word frequencies used to rank dictionary words, from FrequencyWords (based on OpenSubtitles 2018). Licence: CC BY-SA 4.0.
• German word forms for words the dictionary above does not have. Inflection data from the LanguageTool german-pos-dict, used through the RosaeNLG packages german-verbs-dict and german-words-dict. Licence: CC BY-SA 4.0.
• Estonian word forms. Data from Sõnaveeb (Ekilex), by the Institute of the Estonian Language (EKI), through the Ekilex API and through Eesthetic (Estonian Paradigms in Phonemic Notation, v1.0.5), which is built from it. Licence: CC BY 4.0.
• Estonian word frequencies from the Estonian Wordlist Enriched with Ekilex. Licence: CC BY-SA 4.0.

Conjugation software

Verb and noun forms for English, German, and Spanish come from the RosaeNLG packages (Apache License 2.0 and MIT). The Spanish package is based on conjugator by HealthTap, Inc. (Apache License 2.0).

Icons

Icons are from Phosphor Icons, © 2020 Phosphor Icons (MIT licence).

Open-source packages

Ladu is built with many open-source packages, mostly under the MIT, ISC, BSD, and Apache 2.0 licences. The packages that run in your browser, with their licence texts, are in the third-party notices file of the web app. The packages that run on our server are named in the package.json files of the source code.

Ladu's own code

The source code of Ladu is public under the MIT licence. See the LICENSE file in the repository.