Math flash cards

Make cards →

Printable, double-sided math flash cards organized by fact family, not by digit count. Pick a family, set the ceilings, print.

Everything runs in the browser. The PDF is built client-side with pdf-lib, so there is no backend and nothing you type leaves the page.

What it does

• One fact family at a time (+4, -7, and so on), which is how the material is actually taught.
• Separate ceilings for the largest term and the largest answer, so "nothing above 20" means what it says.
• Optional both orders, giving 4 + 9 alongside 9 + 4.
• 4, 6, 9, or 12 cards per sheet, with the type auto-fitted to the widest problem in the deck.
• Answer side prints at adjustable ink darkness so it does not show through thin paper.
• Backs are mirrored across the long edge, so answers land behind their own problems.

Settings live in the URL, so a configuration can be bookmarked or shared.

Printing

Odd pages are problems, even pages are their answers.

• Double-sided printer. Print it all, flipping on the long edge.
• One side at a time. Print the even pages, put the stack back in the tray, print the odd pages.
• Glue. Print single-sided, glue page 1 to page 2, and cut through both.

Running it locally

index.html is the whole site. Open it in a browser, or serve the directory with any static file server. There is no build step.

Files

File
index.html	The entire application
fixtures.json	35 golden cases for the problem selection logic

License

Code is MIT. The PDFs you generate are yours to use however you like, including class sets and district resource folders.