Abstract: A portable postal scale for determining whether the weight of a letter exceeds the maximum for a given amount of postage, for example, one ounce. The scale has a beam in the form of an elongated block with two thicknesses. The flat bottom surface of the thicker portion terminates in a transverse edge that serves as a fulcrum. The thinner end has a clamp for holding a letter, and that end is intended for extension over the edge of a table or desk so that downward movement of the letter is unobstructed. If the letter exceeds the maximum, the thinner end will pivot downward around the fulcrum. The thinner end has a flat bottom surface parallel to the bottom surface of the thicker end and spaced apart a distance corresponding to the maximum letter thickness for a given amount of postage, for example, one-fourth inch.