CodeCards

Practice SQL with worked queries and expected results. Try five cards free; an optional one-time purchase unlocks the full 40-card deck.

CodeCards is a private spaced repetition flashcard app built for programmers. Create decks, write cards in Markdown, review syntax-highlighted code, and let the FSRS scheduler bring each idea back at the right time.

BUILT FOR CODE • Write fronts and backs in Markdown. • Use fenced code blocks with offline syntax highlighting. • Paste formatted HTML for tables and rich notes. • Review with Again, Hard, Good, and Easy grades.

SMART SPACED REPETITION CodeCards uses the FSRS scheduling algorithm to organise due cards and help you retain technical knowledge efficiently. Set your preferred retention and daily new-card limit in Settings.

YOUR CARDS STAY YOURS • No account or sign-in. • No advertising, analytics, tracking, or telemetry. • Study your own cards offline; Apple handles optional purchases and restore online. • All decks and review history stay on your device. • Export and import JSON backups whenever you choose.

See upcoming reviews, streaks, retention, and deck breakdowns in Stats. Use CodeCards on iPhone, iPad, and compatible Apple silicon Macs. SQL PRACTICE PACK Try five original SQLite exercises free. An optional one-time purchase unlocks the full 40-card practice deck, including joins, NULLs, grouping, subqueries and window functions. Each card includes a worked query and expected results. Add the deck, then study and edit it offline. No subscription. Creating your own decks, study and JSON import/export remain free.