Flashcard Size Standard: The Complete Reference
Every standard flashcard size in inches, millimeters, and centimeters — with recommendations for each use case.
Quick Reference Table
| Name | Inches | Millimeters | Centimeters |
|---|---|---|---|
| Standard ★ | 3 × 5 | 76 × 127 | 7.6 × 12.7 |
| Large | 4 × 6 | 102 × 152 | 10.2 × 15.2 |
| Mini | 2 × 3 | 51 × 76 | 5.1 × 7.6 |
| A6 (ISO) | 4.1 × 5.8 | 105 × 148 | 10.5 × 14.8 |
| A7 (ISO) | 2.9 × 4.1 | 74 × 105 | 7.4 × 10.5 |
Standard Size (3×5 inches) — The Most Popular
The 3×5 inch flashcard is the universal standard. It's the size you'll find at Staples, Office Depot, and Amazon. Why is it the standard?
- Portable — a deck of 100 cards fits in your pocket
- Readable — enough space for a word + short definition
- Affordable — cheapest per card at any store
- Compatible — fits standard flashcard organizers and boxes
Best for: vocabulary, definitions, dates, formulas, short facts
Large Size (4×6 inches)
When you need more space — for diagrams, longer definitions, or illustrations — the 4×6 inch card is the next step up.
Best for: anatomy diagrams, math proofs, longer explanations, mind maps
Mini Size (2×3 inches)
The compact option for quick-recall facts. These are small enough to carry hundreds at a time.
Best for: multiplication tables, chemical symbols, country capitals, quick-reference data
ISO Paper Sizes (A6, A7)
In countries that use the ISO 216 paper standard (most of the world outside the US), flashcards are commonly cut from A-series paper:
- A6 (105×148mm) — similar to the US "large" size, common in Europe and Japan
- A7 (74×105mm) — similar to the US "standard" size
You can cut an A4 sheet into 8 × A7 flashcards or 4 × A6 flashcards with minimal waste.
How to Cut Flashcards from A4/Letter Paper
From A4 (210×297mm):
- Cut into 8 cards → each ≈ 74×74mm (mini square)
- Cut into 4 cards → each ≈ 105×148mm (A6)
- Cut into 2 cards → each ≈ 148×210mm (A5 — large study sheets)
From US Letter (8.5×11 in):
- Cut into 6 cards → each ≈ 2.8×3.7 in (mini)
- Cut into 4 cards → each ≈ 4.25×5.5 in (between standard and large)
- Cut into 2 cards → each ≈ 5.5×8.5 in (half-sheet study guide)
Print and Fold: An Easier Alternative
Instead of cutting individual cards, try the fold method: print your flashcards in an aligned two-column format, then fold the paper along the center. The front (question) appears on the left, and the back (answer) on the right.
FlashCard Studio can export your entire deck in this fold-ready format automatically — just click "Export Markdown" and print.