110-lb index cards are thick enough for highlighters

110-lb index cards are the sweet spot for studying vocab—standard, sturdy, and no highlighter bleed-through.

Most index cards you see at the checkout aisle are actually 67-lb or 80-lb stock. Those are fine for quick notes, but a wet highlighter soaks right through and ruins the other side. The good stuff is 110-lb. It’s the standard “heavyweight” weight for flashcards, and it holds up to highlighters, gel pens, and even most markers without ghosting.

When you’re shopping, just check the package. Look for “110 lb” or “heavyweight” on the box. Oxford makes a reliable 110-lb ruled index card, and Staples has its own version that works just as well. Avoid the dollar-store packs—they’re usually