Calculate Rectangular Hollow Section (RHS) weight in kg/m and total kg instantly. Supports IS 4923 grades with optional corner radius. Enter depth, width, wall thickness and length — results in seconds.
Enter RHS dimensions, choose whether to include corner radius, select material and get complete weight results instantly.
Understanding Depth (D), Width (B), Wall Thickness (t) and Corner Radius (R) in a Rectangular Hollow Section
For IS 4923 standard sections, outer corner radius R = 2t and inner corner radius ri = t. The corner radius reduces the cross-sectional area compared to sharp-corner hollow sections.
Step-by-step guide for accurate Rectangular Hollow Section weight calculation as per IS 4923 India
Use Without Corner Radius for quick estimates or when corner radius is unknown. Use With Corner Radius (IS 4923) for exact results that match mill datasheets and BIS published values.
Enter Depth (D) as the longer side and Width (B) as the shorter side in millimetres. For standard IS 4923 RHS like 100×50 — D = 100 mm, B = 50 mm. If D = B, use the SHS calculator instead.
Enter wall thickness (t) in mm. Common IS 4923 RHS wall thicknesses range from 2.0 mm to 10 mm. The same wall thickness applies to all four sides in standard hollow sections — refer to the reference table below for standard sizes.
In IS 4923 mode, enter the outer corner radius. The default is R = 2 × t for hot-formed sections. The inner radius (ri = R − t) is computed automatically. Leave as default if checking against standard section tables.
Enter length per piece in metres. Standard Indian market RHS lengths are 6 m and 12 m. Enter quantity for total batch weight — useful for procurement, freight and project cost estimation.
Results include kg/m (compare with mill datasheet), weight per section, total kg, metric tonnes (MT), cross-section area (mm²) for structural design, and outer perimeter for surface area and paint estimation.
Both calculation methods explained clearly with worked examples
The term 2t(D + B − 2t) treats the cross-section as two rectangular strips — one pair for depth walls, one pair for width walls, minus the four corner overlaps counted twice. This is fast and accurate to within 1–2% for most standard sections.
The correction term (4 − π) × ri² removes exactly the four square corner areas that are replaced by circular arcs. This is the formula used in IS 4923:1997 and matches the published section tables from SAIL, APL Apollo and Tata Structura within ±0.1%.
Outer perimeter = 2(D + B). This is used for paint and coating estimation. One litre of paint covers approximately 10–12 m² — multiply perimeter (m) × total length × quantity to get surface area in m², then divide by the paint coverage rate.
ri = 8 − 4 = 4 mm
Area = 2×4×(100+50−8) − 0.8584×16 = 1136 − 13.73 = 1122.3 mm²
kg/m = 1122.3 × 7.85 ÷ 1000 = 8.81 kg/m
Per section = 8.81 × 6 = 52.88 kg
Total = 52.88 × 20 = 1057.6 kg = 1.058 MT
Rectangular Hollow Section weight per metre — IS 4923:1997, density 7.85 g/cm³, outer corner radius R = 2t
| D × B (mm) | t (mm) | R outer (mm) | ri inner (mm) | Area (mm²) | kg/m | 6 m Weight (kg) | IS Grade |
|---|---|---|---|---|---|---|---|
| 40 × 20 | 2.0 | 4.0 | 2.0 | 216.6 | 1.70 | 10.20 | YSt 210 |
| 50 × 25 | 2.0 | 4.0 | 2.0 | 272.6 | 2.14 | 12.84 | YSt 210 |
| 50 × 25 | 2.5 | 5.0 | 2.5 | 334.2 | 2.62 | 15.74 | YSt 210 |
| 60 × 40 | 3.0 | 6.0 | 3.0 | 552.7 | 4.34 | 26.04 | YSt 240 |
| 75 × 45 | 3.0 | 6.0 | 3.0 | 672.7 | 5.28 | 31.68 | YSt 240 |
| 80 × 40 | 3.0 | 6.0 | 3.0 | 672.7 | 5.28 | 31.68 | YSt 240 |
| 80 × 40 | 4.0 | 8.0 | 4.0 | 878.3 | 6.89 | 41.36 | YSt 240 |
| 100 × 50 | 3.0 | 6.0 | 3.0 | 832.7 | 6.54 | 39.22 | YSt 240 |
| 100 × 50 | 4.0 | 8.0 | 4.0 | 1122.3 | 8.81 | 52.88 | YSt 240 |
| 100 × 50 | 5.0 | 10.0 | 5.0 | 1375.7 | 10.80 | 64.80 | YSt 310 |
| 120 × 60 | 4.0 | 8.0 | 4.0 | 1362.3 | 10.69 | 64.17 | YSt 240 |
| 120 × 60 | 5.0 | 10.0 | 5.0 | 1675.7 | 13.15 | 79.01 | YSt 310 |
| 150 × 75 | 5.0 | 10.0 | 5.0 | 2125.7 | 16.68 | 100.10 | YSt 310 |
| 150 × 100 | 5.0 | 10.0 | 5.0 | 2375.7 | 18.65 | 111.88 | YSt 310 |
| 150 × 100 | 6.0 | 12.0 | 6.0 | 2821.3 | 22.15 | 132.88 | YSt 310 |
| 200 × 100 | 5.0 | 10.0 | 5.0 | 2875.7 | 22.57 | 135.45 | YSt 310 |
| 200 × 100 | 6.0 | 12.0 | 6.0 | 3421.3 | 26.86 | 161.15 | YSt 310 |
| 200 × 100 | 8.0 | 16.0 | 8.0 | 4478.3 | 35.15 | 210.88 | YSt 310 |
| 250 × 150 | 6.0 | 12.0 | 6.0 | 4621.3 | 36.28 | 217.65 | YSt 310 |
| 250 × 150 | 8.0 | 16.0 | 8.0 | 6078.3 | 47.71 | 286.30 | YSt 310 |
| 300 × 150 | 8.0 | 16.0 | 8.0 | 6878.3 | 53.99 | 323.92 | YSt 310 |
| 300 × 200 | 10.0 | 20.0 | 10.0 | 9475.7 | 74.38 | 446.27 | YSt 310 |
* Values based on IS 4923:1997 with outer corner radius R = 2t, density 7.85 g/cm³. Actual mill weights may vary by ±2.5% as per BIS IS 4923. Verify with supplier MTR. Stockists: APL Apollo, Tata Structura, JSPL, SAIL, Shyam Steel. See also: RHS SHS with Corner Radius Calculator.
Standard density values for hollow section weight calculation across Indian engineering and fabrication industry
All three IS 4923 yield grades (YSt 210, YSt 240, YSt 310) have identical density of 7.85 g/cm³ — the grade only determines minimum yield strength, not weight. Always confirm density with mill test certificate for critical applications per BIS standards.
Where Rectangular Hollow Sections are used across India's construction, manufacturing and infrastructure sectors
RHS sections are the backbone of pre-engineered industrial sheds across India. Sizes like 150×75, 200×100 and 250×150 mm are used for roof purlins, side rails and primary structural frames in factories and warehouses.
India's solar capacity addition programme (targeting 500 GW by 2030) uses millions of tonnes of RHS sections for ground-mounted tracker systems. RHS 80×40 and 100×50 are standard sizes in solar mounting structures.
Indian metro rail projects (Delhi, Mumbai, Bangalore, Hyderabad, Chennai) use RHS sections for platform canopies, pedestrian bridges, staircase frames and equipment enclosures — all requiring accurate weight for structural analysis.
Truck body builders in Pune, Coimbatore and Rajkot use RHS sections for tipper body frames, container sub-frames and flatbed structures. IS 4923 YSt 310 is preferred for its higher strength-to-weight ratio.
RHS 40×20 and 60×40 mm sections are extensively used for industrial compound gates, security grilles and boundary fencing across India. APL Apollo's Tulsi brand dominates this market segment nationally.
Farm implement manufacturers in Punjab, Haryana and Maharashtra use RHS sections for tractor implements, seed drills, cultivators and equipment frames — requiring cost-effective weight calculation for competitive pricing.
Best practices used by Indian structural engineers, quantity surveyors and steel procurement teams
When placing orders or verifying supplier invoices, always use the With Corner Radius (IS 4923) mode. Indian mills supply sections per IS 4923 — the published kg/m values in their catalogues already include corner radius deduction. Using sharp-corner values overestimates weight by 1–2%, leading to incorrect cost calculations.
Always enter the longer dimension as Depth (D) and the shorter as Width (B). A 100×50 RHS and a 50×100 RHS have the same weight per metre but very different bending stiffness. Correct orientation is critical when specifying sections for structural design using IS 800:2007.
IS 4923 allows ±2.5% weight tolerance per section. For site procurement, always add a 3–5% buffer over the calculated total weight to cover mill tolerance, cutting losses and damaged pieces. For large projects above 50 MT, request weigh bridge certified delivery notes from suppliers.
Use the Perimeter output (mm) from this calculator to estimate paint requirements. Surface area = perimeter (m) × total length (m) × quantity. At 12–14 m² per litre for standard primer, this gives exact paint quantity for budgeting. For galvanised RHS, surface area determines hot dip galvanising cost at approximately ₹18–22 per kg or ₹8–10 per m² in India 2026.
As of 2026, IS 4923 RHS sections are priced approximately ₹65,000–₹80,000 per MT ex-Mumbai/Delhi depending on size, grade and quantity. Smaller sizes carry a premium. APL Apollo, Tata Structura and JSPL are price leaders. Always get a fresh stockist quote — Indian steel prices change weekly with HRC coil prices.
For structural applications governed by IS 800:2007, always request the Mill Test Certificate (MTC) from your supplier. The MTC confirms actual weight per metre, yield strength, tensile strength and chemical composition — all required for IS 4923 compliance on government and infrastructure projects in India.
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