Everyone is familiar with the classic two-tone eraser—the pink side and the mysterious blue side. For years, a popular belief has circulated: the blue side is meant to erase pen ink. Who hasn’t furiously scrubbed their notebook, hoping to erase an ink mistake, only to be left with a torn-up page?

So, What Is the Blue Part Really For?

The Myth of the Pen: Why Did This Belief Take Hold?
For generations, people have believed that the blue side erases pen ink, probably because of its rougher, more abrasive texture. And many of us have tested the theory… usually ending up with more holes in our paper than actual erased ink!

But here’s the truth: the blue part of the eraser is not designed to erase ink. Ink seeps into the fibers of the paper, unlike pencil marks, which stay on the surface. Rubbing harder won’t remove the ink—it’ll just destroy your page.

The Real Purpose of the Blue Side

Contrary to popular belief, the blue side is still meant for pencil, but on specific types of surfaces. Because it’s firmer and more abrasive, it works best on:

Thick or textured paper, like Canson or other artist-grade drawing paper

Cardboard or rigid surfaces where pencil tends to stick more

Walls, especially when cleaning off little kids’ doodles

Meanwhile, the pink side is softer and better suited for standard paper, like notebooks, printer paper, or binder sheets.

What the Experts Say