Will Mechanical Pencils Work on Scantrons?

But even if they don't use modern scantron machines, you should actually still be able to use a mechanical pencil and have it be read by the machine correctly, just so long as you use the correct lead weight. ... (You can read more about lead grades and mechanical pencils here if you are interested.)

Do mechanical pencils count as number 2?

2 pencil and mechanical pencils are not always regulated as No. 2. In addition, they are thin and prone to breaking, which means your marks may not be as readable as the thicker, darker marks you can achieve with an old-school number 2 pencil.

Why do you have to use #2 pencils for tests?

No. 2 pencils were required to fill in the circles on the sheet because the graphite in the pencil is an opaque substance that absorbs the light that hits it. Most modern sheets are now read by machines that measure lightness and darkness. These machines (technically) do not require the use of No.