Engineering calculations, built for design engineers

The suite covers four engineering disciplines. HVAC includes psychrometrics, cooling load, duct and pipe sizing, fans, pumps, chiller and chiller-plant selection, cooling towers, heat transfer, insulation, dehumidification, humidification, electric heating, evaporative cooling, refrigeration cycles and pressurisation. Fire protection covers fire-water storage, pump duty, main, standby and jockey pump sizing, sprinkler spacing and pipe sizing, hydrant counts and ring-main sizing. Public health engineering covers water demand, storage, pumping, hot water, drainage, venting, storm water, rainwater harvesting and sewage treatment capacity. Electrical covers load estimation, cable and busbar sizing, voltage drop, transformers, DG sets, UPS and battery sizing, motors, short-circuit levels, power-factor correction, earthing, lighting, cable trays, protection coordination and solar PV. Cleanroom tools cover ISO classification, air change rates, FFU selection and particle counts.

Calculations are deterministic. The same inputs always produce the same output, because each calculator is a closed-form implementation of a published equation or table — not a statistical estimate and not a language-model guess. Each result page lists the assumptions applied, the validation limits on the inputs and a set of engineering checks that flag values falling outside normal design practice.

Reference methods are drawn from ASHRAE Handbook chapters and ASHRAE standards, SMACNA duct construction practice, ISO 14644 for cleanrooms, CTI for cooling towers, the Hydraulic Institute and CIBSE for pumping, IEC, IEEE and the relevant IS codes for electrical design, and the National Building Code of India, IS codes and NFPA standards for fire protection and plumbing. Because standards are revised, every calculator asks you to confirm the edition adopted by your project or authority having jurisdiction.

The platform is aimed at design consultants, contractors, facility engineers and engineering students who need defensible preliminary and system-level numbers quickly. Typical use is early-stage sizing, design cross-checking, tender review and verifying a vendor submission against an independent calculation.

A selection of introductory calculators is free and open without registration. A free account unlocks the full suite, saved projects and PDF calculation reports suitable for attaching to design documentation.

Alongside the calculators, the platform publishes Engineering Intelligence briefs on critical design decisions and a Knowledge Base of longer technical articles. Both focus on major design basis, failure consequences and verification actions rather than minor detailing, and both cite the standards that govern the topic.

The platform is independently built and maintained. Questions, corrections and feature requests are welcome at mepenggsuite@gmail.com. If you believe a calculation or a standards reference is wrong, please tell us — technical corrections are treated as a priority.