Weight of hex bolt assemblies — bolt, nuts and washers — for any size M6 to M64 and length. For procurement, galvanising and dispatch weights. Free, instant, no login.
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Try AI Estimation free| Size × length | Bolt only | +1 nut, 2 washers |
|---|---|---|
| M12 × 40 | ≈ 52 g | ≈ 75 g |
| M16 × 50 | ≈ 118 g | ≈ 172 g |
| M20 × 60 | ≈ 250 g | ≈ 350 g |
| M24 × 80 | ≈ 462 g | ≈ 637 g |
| M30 × 100 | ≈ 913 g | ≈ 1,255 g |
Weights follow the geometry: shank = π/4 × d² × L × 7.85×10⁻⁶ kg, plus a hex head of ≈1.22·d³, nut ≈0.93·d³ and washer ≈0.33·d³ (DIN 931/934/125 proportions in steel). Real manufactured weights vary about ±5% with thread length and head tolerance.
An M20 × 60 hex bolt is roughly 250 g; a full assembly with one nut and two washers is about 350 g. Each extra 10 mm of length adds ~25 g.
Galvanising is priced per kg, freight is booked by weight, and dispatch lists need it — 5,000 M20 assemblies is ~1.75 tonnes of steel.
It's a geometric approximation to DIN proportions, typically within ±5%. For contractual weights use the manufacturer's certified table.