Hex Bolt / Nut / Washer Weight Calculator Online (M6-M20 Chart)

Hex bolt / Nut / Washer Weight Calculator (M6-M20 Chart)

Fasteners are inexpensive individually but consumed in volume, so buyers and logisticians constantly estimate cost and freight by weight. Weighing piece by piece is impractical and printed charts are cumbersome - the online calculator on this page estimates unit weight and batch total weight from type, size and material, covering hex bolts (GB/T 5783), hex nuts (GB/T 6170) and plain washers (GB/T 97.1).

The method multiplies standard geometric volume by material density: a hex bolt equals the shank cylinder plus the hex head prism, V = PI/4 x d^2 x L + 0.866 x s^2 x k. Real parts weigh less than raw geometry due to head chamfers and thread relief, so this tool applies calibration factors (shank x0.88, head x0.72, nut x0.90) benchmarked against the official GB/T 5783 mass tables, keeping error within about 10%. Stainless 304 is about 1% heavier than carbon steel, brass about 8% heavier, aluminum about 66% lighter; hot-dip galvanizing adds roughly 4-5%.

Theoretical weight suits purchasing estimates and freight quotes; actual weighing governs trade settlement. For batch purchasing or custom-length bolts, use the full weight calculator. Zhuhai Jiali Hardware manufactures precision screws and custom fasteners - contact us for volume pricing.