Wind Pressure Calculator (IS 875)
Design wind pressure from basic wind speed with terrain/height factor.
47 m/s gives 1.33 kN/m² — wind pressure scales with speed SQUARED, so the 55 m/s cyclone zone carries 37% more pressure than Delhi. Cp shape factors then split it over surfaces.
Formula
Wind Pressure Calculator (IS 875) is a free wind pressure for structural engineers, fabricators and site engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Wind Pressure Calculator (IS 875)
Design wind pressure from basic wind speed with terrain/height factor. The calculation implements V_z = V_b·k₁k₂k₃; p_z = 0.6·V_z² (N/m²) (IS 875 Part 3:2015). 47 m/s gives 1.33 kN/m² — wind pressure scales with speed SQUARED, so the 55 m/s cyclone zone carries 37% more pressure than Delhi. Cp shape factors then split it over surfaces.
How to use Wind Pressure Calculator (IS 875)
- 1Enter Basic wind speed V_b in m/s (India zones: 33–55 m/s (Delhi 47, Chennai 50, Mumbai 44)).
- 2Enter Terrain-height factor k₂ (10 m, terrain 2 ≈ 1.0; tall/open higher).
- 3Enter Risk factor k₁ × topography k₃.
- 4Read Design speed V_z, Design pressure p_z instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Wind Pressure Calculator (IS 875)?
- ✓Implements the standard formula — V_z = V_b·k₁k₂k₃; p_z = 0.6·V_z² (N/m²)
- ✓Reference cited on-page: IS 875 Part 3:2015
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Wind Pressure Calculator (IS 875) use?+
It computes V_z = V_b·k₁k₂k₃; p_z = 0.6·V_z² (N/m²), per IS 875 Part 3:2015. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
47 m/s gives 1.33 kN/m² — wind pressure scales with speed SQUARED, so the 55 m/s cyclone zone carries 37% more pressure than Delhi. Cp shape factors then split it over surfaces.
Can I use this for real structural design?+
It implements the exact textbook/code formula cited below the result and is ideal for sizing, checking and learning. Final designs should be verified by a qualified engineer against the full code with all load cases.
Is the Wind Pressure Calculator (IS 875) free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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