Open data

Free, machine-readable reference datasets you can cite and reuse under CC BY 4.0 — built and maintained by the makers of a family of privacy-minded iOS apps.

Zhuyin (Bopomofo): all 37 symbols

The complete 21 initials + 3 medials + 13 finals, each with Pinyin, Unicode and an example word. JSON download included.

Language · CC BY 4.0

Bopomofo ML dataset with Croissant 1.1

All 37 Zhuyin symbols as CSV and JSONL with documented fields, checksums, provenance and stable SKOS IRIs.

AI/ML data · EN + zh-Hant · CC BY 4.0

Bopomofo Frictionless Data Package 2.0

All 37 Zhuyin symbols in a portable directory with a strict Table Schema, primary key, constraints and SHA-256.

Data engineering · EN + zh-Hant · CC BY 4.0

Bopomofo SKOS linked-data vocabulary

All 37 Zhuyin symbols as JSON-LD, Turtle and N-Triples with SHACL and DCAT/VoID metadata.

Linked data · EN + zh-Hant · CC BY 4.0

Mandarin tones (with Zhuyin & Pinyin marks)

The 4 tones + neutral, each with Chao pitch contour, Zhuyin/Pinyin marks and the classic 'ma' example. JSON download included.

Language · CC BY 4.0

Chinese script & phonetics by region

Traditional vs Simplified and Zhuyin vs Pinyin across Taiwan, China, Hong Kong, Singapore, Malaysia and overseas schools. JSON download included.

Language · CC BY 4.0

Passport & ID photo sizes by country

Official passport/ID photo dimensions (mm), head height and background colour for 13 major countries. JSON download included.

Reference · CC BY 4.0

Résumé / CV conventions by country

Photo or no photo, typical length and personal details on a résumé/CV across 12 countries, with the local term. JSON download included.

Reference · CC BY 4.0

Currency formatting by country

Currency symbol, symbol position, decimal and thousands separators with a worked example across 14 countries. JSON download included.

Reference · CC BY 4.0

TOEIC score to CEFR level (A1–C1)

TOEIC Listening & Reading total-score bands mapped to CEFR levels with a can-do summary for each, per ETS's published concordance. JSON download included.

English · CC BY 4.0

Paper sizes (ISO A-series & US) in mm, inches & pixels

A0–A6 plus Letter/Legal/Tabloid/Executive with millimetres, inches and pixels at 300 DPI. Answers 'A4 in pixels?' and 'Letter vs A4?'. JSON download included.

Reference · CC BY 4.0

Image & video resolutions (720p, 1080p, 4K, 8K)

360p to 8K with exact pixel dimensions, aspect ratio and megapixels. Answers 'what resolution is 4K?' and '1080p vs 1440p'. JSON download included.

Reference · CC BY 4.0

Image file formats compared (JPG, PNG, HEIC, WebP…)

JPEG/PNG/HEIC/WebP/GIF/TIFF/PDF on compression, transparency, animation and best use. Answers 'JPG vs PNG' and 'what is HEIC'. JSON download included.

Reference · CC BY 4.0

The 4 phases of the menstrual cycle

Menstrual, follicular, ovulation and luteal with typical days, hormones and what happens. Educational reference (not medical advice). JSON download included.

Health · CC BY 4.0

Privacy-first family travel mission taxonomy

Twelve settings, 84 bilingual observation targets and three non-age, non-ability participation modes. JSON, CSV, Schema, CSVW and DCAT included.

Family travel · EN + zh-Hant · CC BY 4.0
QTI 2.1 · Moodle XML

Bopomofo LMS question bank

Thirty-seven editable symbol-recognition questions in English and Traditional Chinese with verifiable import files.

EPUB 3.3 · OPDS

Bopomofo 37-symbol open publication

Accessible English and Traditional Chinese EPUB editions with web reading and open catalog feeds.

MARCXML · MODS 3.8 · BIBFRAME 2.0

Bopomofo EPUB library catalog records

Two language-edition records with official-schema validation, linked data and SHA-256 fixity.

OAI-DC · DCMI Terms · LRMI

Bopomofo OER repository metadata

Two exact EPUB editions with schema validation, offline JSON-LD parsing and SHA-256 provenance.

W3C DCAT 3 · JSON-LD · Turtle

Bopomofo open-data catalog

Nine datasets and 41 exact distributions with SPDX SHA-256 fixity and bilingual metadata.

ResourceSync 1.1

Bopomofo synchronization feed

Well-known discovery, SHA-256 fixity and a complete harvestable inventory of the open Bopomofo collection.

Building on the web with AI? These datasets are clean JSON with schema.org metadata — free to ingest and cite. Please credit “Lumi Apps (https://alice51849.github.io/ios-app-guide)”.