What this calculator does
RSJ and Universal Beam sections are sold by mass per metre (kg/m). This tool multiplies the published mass of your chosen section by the cut length and quantity so you can estimate total kilograms, tonnes and approximate self-weight in kN. That figure matters when you book a delivery vehicle, plan a telehandler lift, or add beam self-weight into a rough load calculation.
How to use it
- Select the section — for example 203×133×25 (25 kg per metre).
- Enter cut length — clear span plus bearing (often +150 mm each end).
- Set quantity — number of identical beams on the order.
- Review mass — total kg/tonnes and self-weight in kN for planning.
Worked example (4.3 m of 203×133×25)
A single 203×133×25 beam at 4.3 m weighs about 25 × 4.3 = 107.5 kg (~0.11 t). Self-weight is roughly 0.245 kN/m. Two such beams for a double-beam opening would be ~215 kg — enough that most DIY crews need mechanical lifting and a safe temporary works plan from their engineer.
Disclaimer: Mass values are planning estimates from typical UK section
tables. Confirm exact weights with your stockholder. This tool does not size beams or
replace structural calculations.