Licences & privacy
What the site stores (very little), and where its data comes from.
Privacy
- No accounts, ads, tracking cookies or analytics.
- The text you enter is processed on your device and never sent anywhere.
- Your browser (localStorage) keeps only what you choose: settings (theme, Simplified / Traditional, voice, practice-sheet options), memory stories in Character breakdown and known words in the Reader. Clearing the site's data in your browser removes it all; the last two can be exported as TSV.
- The site is hosted on Vercel. Like any web server, Vercel keeps technical logs (IP address, browser, pages loaded) to run the service; we do not use them to track you.
- Online voices are off by default. Only if you turn them on in the voice settings does your browser send the single word you click to the voice provider (Google or Microsoft).
- Links to other sites (GitHub, Anki, the data projects) follow those sites' own policies.
Licences
The Hán Ngữ Studio source code is under the MIT License: you may use, change and share it, commercially too, as long as you keep the copyright notice.
The bundled data keeps the licence of each source below, not MIT. Data built from CC BY-SA sources (Vietnamese meanings, English meanings, pronunciation files) is shared under that same licence.
Data sources
HSK 3.0 (GF 0025-2021) · ivankra/hsk30
Used for: HSK 3.0 levels, Pinyin and part of speech of words (PRC Ministry of Education).
Licence: MIT
Used for: Vietnamese meanings and measure words (machine-translated from CC-CEDICT and reviewed): first three senses for HSK words, the whole dictionary for other words in the Reader.
Licence: CC BY-SA 4.0
Used for: English meanings.
Licence: CC BY-SA 4.0
Used for: Example sentences; sentences marked “machine-translated” were translated with Google Translate.
Licence: CC BY 2.0 FR
Used for: Component breakdown and character formation (Character breakdown).
Licence: LGPL-3.0+
Used for: Strokes for Stroke order, Practice sheet and Character breakdown.
Licence: Arphic Public License
audio-cmn · Yue Tan, Chen Wang, Hugo Lopez
Used for: Word and syllable recordings (unchanged, only repacked).
Licence: CC BY-SA
Used for: The characters under each radical.
Licence: Unicode License v3
Used for: Wubi codes.
Licence: MIT
hanviet-pinyin-wordlist · Phong Phan
Used for: Hán Việt readings of characters (some edited).
Licence: MIT
SUBTLEX-CH · Cai & Brysbaert (2010), PLoS ONE 5(6): e10729
Used for: Order of common characters and words (ranks only; the frequency figures are not redistributed).
Licence: —
Used for: Word list for segmentation: CC-CEDICT headwords ordered by SUBTLEX-CH frequency.
Licence: CC BY-SA 4.0
Used for: Simplified · Traditional · Japanese row in Character breakdown: the Simplified, Taiwan Traditional and Japanese (shinjitai) form of each character.
Licence: Apache-2.0
Wikimedia Commons · Ancient Chinese characters project
Used for: Through the ages row in Character breakdown: oracle bone, bronze, great seal and small seal drawings (SVG).
Licence: Public domain · CC0 1.0
Used for: Libraries running in the browser: stroke animation, Pinyin, Simplified / Traditional conversion, icons.
Licence: MIT · Apache-2.0 · ISC · public domain (SQLite)
Be Vietnam Pro, Noto Sans/Serif SC/TC, LXGW WenKai TC, Ma Shan Zheng
Used for: Interface and practice-sheet fonts.
Licence: SIL OFL 1.1
Compiled by Hán Ngữ Studio
Names and meanings of the 214 radicals (checked against PREP's list), the example sentences with hand-checked translations, the stories in Stories (text, translations and culture notes), the suggested memory tricks in Character breakdown (drafted with AI help and reviewed over time; unreviewed ones are labelled), and the edits made to the sources above.