Pencil Hardness Converter

Pencils are graded on two scales: the European HB system and the US number system. The HB system is used worldwide, while the US number system is common in American schools and offices.

The HB graphite scale: The scale runs from hard (H) to black/soft (B), with F (fine point) and HB in the middle.

• H grades (2H, 3H, 4H, etc.): Harder lead, lighter marks, holds a sharp point longer.
• B grades (2B, 3B, 4B, etc.): Softer lead, darker marks, wears down faster.
• Higher numbers mean more extreme hardness or softness.

Complete comparison table:

US number to HB equivalents:

What determines pencil hardness? The graphite-to-clay ratio in the pencil core determines its hardness. More clay makes the lead harder and lighter (H grades). More graphite makes the lead softer and darker (B grades). HB has a balanced mix of graphite and clay.

Practical guide for choosing pencils:

• Standard writing: HB or #2 is the universal choice. This is required for scantron/standardized test forms.
• Sketching and drawing: Keep a range from 2H (light outlines) to 6B (deep shadows).
• Technical drafting: Use H to 4H grades for precise, light lines that do not smudge.

Three pencils cover almost everything a beginner needs: 2H, HB, 2B. Light construction lines, normal working, and shadow. Buying a 24-pencil set before you know which end of the scale you actually reach for is a common and expensive mistake, and most people find they use four or five of them.

A warning about the two ends. H grades bite. Press a 4H hard enough to see the line and it scores a groove into the paper that no eraser will lift, and that groove shows through anything you shade over it later. B grades have the opposite problem: 6B and softer smear if your hand so much as passes over them, which is why left-handed artists working left to right, and right-handed artists working right to left, end up with grey palms and muddy paper. A sheet of scrap under the drawing hand solves it.

Brands do not agree with each other. The HB scale is a convention, not a measured standard, so one maker’s 2B lands somewhere near another’s B. The differences are largest at the extremes and can be a full grade. Staedtler and Faber-Castell run on the harder side of their labels, Derwent on the softer. If a drawing matters, stay within one brand for the whole thing.

A different “pencil hardness” entirely: ASTM D3363. If you arrived here from paint, coatings or industrial finishing, the term means a surface hardness test rather than a drawing pencil. A set of graded pencils is pushed across the coating at 45 degrees under a 750 g load, starting soft and working harder. The hardest pencil that does not gouge the film is the coating’s rating. The same 9B to 9H scale is used, so a finish rated “2H” resists a 2H pencil but is marked by a 3H. Furniture and cabinet coatings typically land at H to 2H, automotive clear coats near 2H to 4H. Note the test scale runs the same direction as the pencil scale, so a higher H number is a harder, more scratch-resistant finish.