0.7

Along with 0.5, the most common size of tip, ideal for all uses from writing to drawing. If you press hard while writing and make large letters, 0.7 is recommended, otherwise 0.5.

For writing, the values F, HB, B, 2B, 3B are recommended. The higher the value of B, the softer the pencil tip and the more intense the black color. The higher the value of H, the harder the tip and the lighter the black color.