How do I find the weight per meter of a steel profile?

Every steel profile has a weight per meter (kg/m) published in its standard datasheet — it equals the cross-sectional area (in m²) multiplied by steel density (7,850 kg/m³). For example, an ISMB 400 has area 7,755 mm² = 0.007755 m², weight = 0.007755 × 7850 ≈ 61 kg/m. CalcSteel stores the exact manufacturer weight for all 1,140 profiles in its catalog (access via /profiles) — just search for the profile name and the weight appears in both kg/m and lb/ft. For custom or built-up sections, compute area × density. For thin-walled cold-formed sections, the weight is sometimes lower than area × density because of material loss in forming.