Key difference: The main difference between an HB and B pencil is that the HB pencil is a medium range lead, whereas the B pencil has a softer lead.

A Pencil is a popular tool used for writing as well as drawing purposes. Pencils are made of wood with a graphite core inside; it is actually the combination of clay and finely grounded graphite, mixed with water and pressed together at high temperatures to make thin pencil rods. This process was developed by Nicolas-Jacques Conté, a Frenchman, in 1795, and it is still the widely used method by the pencil manufactures.

Pencils differ according to their different shades of color, and based on the hardness of their lead are classified into hard and soft leads. Terms such as HB, B, F and H are used. Here, the H stands for ‘hard’ which is designated for hard leads, and B stands for ‘black’ which is designated for softer leads. Also, any number in front of HB, or B, or H simply indicates the shade of the lead.

The term ‘HB’ is universal and is usually printed on all pencils. It means that the pencil is hard and black, and depicts the hardness and the nature of the color used in the pencil. According to the shade chart, the HB pencils range in the middle of the chart. They are known to be standard and are the preferred grade for general writing purposes. It is one of the most popular in the lead hardness categories. It has a good tensile strength, and has a smooth feel while writing. The HB pencil has a limited amount of clay, which gives a medium line density while using, and is mediocre in shade. It is easy to erase, which is why it is used by children to improve their 'penmanship' in school.

Along with the HB grading system, there is BB grading system also used. Here, the term “B” stands for successively softer leads. Soft pencils are known to give darker shades. Also, depending on the shade, pencils are numbered according to the color of the different shades. They make a dark line with heavy density. They give a fairly darker shade, which makes it hard to erase and leave their mark on the paper. These pencils contain a small quantity of clay which makes the lead soft and ideal for bold or thick writing. It makes the letters easier to read and have a smooth feel while writing. It is popular and widely used by artist for their sketches and paintings.

These grading systems can be a little confusing, but they help and make it easy to pick and choose the right pencil when required. 

Comparison between HB and B Pencil Lead:

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