Stop guessing.
Start calculating correctly.
20+ professional engineering calculators, step-by-step guides, and ready-to-use templates — based on NFPA, ASHRAE, IS standards. Built for real-world design and site work.
No software needed·Browser-based·Standards-referenced
A wrong calculation in MEP costs far more than the time you “saved”
Undersized sprinkler pipes
A density/area calculation missed by 10% can mean a failed hydraulic test — and an entire re-pipe on site.
Oversized HVAC equipment
Short cycling, humidity problems, and energy waste — all from tonnage guesswork instead of proper load calc.
Voltage drop ignored
Motor failures, breaker trips, and non-compliant installations trace back to skipping wire size calculations.
Not just a calculator — a complete engineering workflow
Every tool explains the method, cites the standard, and produces outputs you can drop directly into a submittal.
Professional Calculators
20+ tools for HVAC, Fire, Electrical, Plumbing, Civil — with fitting losses, unit toggles, and code references.
Report-Ready Outputs
Calculation sheets formatted for engineer review and client submittals — copy paste into your report.
Explain-as-you-go Steps
Every input is explained with the underlying formula and standard. Juniors learn; seniors review faster.
Scenario-Based Quizzes
Test yourself on real situations — NFPA 13, ASHRAE 62.1, NEC wire sizing — not just definitions.
Standards Quick Finder
Wizard-based tool that maps your domain + goal to the right calculator in under 30 seconds.
BOQ / Quantity Tools
Steel, concrete, earthwork, tiles — multi-element bill outputs with regional cost estimates.
Popular Calculators
Filter by discipline — or use the search bar (press /) to find any tool instantly.
Latest Engineering Guides
Deep dives written for practitioners — not textbooks. Every guide has worked examples and references to the relevant standard.
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What professionals say
“The sprinkler hydraulics calculator matched our hand calc to within 2%. It’s become the first sanity check on every fire job.”
“Finally, a duct sizing tool that includes fittings and pressure drop — not just velocity. Saves me 30 minutes on every HVAC job.”
“I use the earthwork cut/fill and concrete calculators daily on site. The swell & shrink factors are exactly what my QS team needed.”
One bad calculation costs more than a year’s Pro subscription
Choose the tier that matches your work. Cancel anytime.
- ✓ Explain-as-you-go content
- ✓ Quantity calculators (tiles, concrete, steel)
- ✓ Bernoulli, psychrometrics, heat transfer basics
- ✓ Perfect for students and QSs
- ✗ Advanced NFPA/ASHRAE tools
- ✗ Report-ready outputs
- ✗ Duct sizing with fittings
- Everything in Basic, plus:
- ✓ Sprinkler hydraulics (NFPA 13)
- ✓ Duct sizing with fittings + pressure drop
- ✓ Ventilation / ACH (ASHRAE 62.1)
- ✓ Smoke exhaust fan sizing (NFPA 92)
- ✓ Wire size & voltage drop (NEC)
- ✓ Transformer sizing
- ✓ Report-friendly outputs for submittals
- ✓ Priority email support
- ✓ All future Pro tools included
- ✓ Everything in Pro
- ✓ 5+ seats, centralised billing
- ✓ Usage analytics dashboard
- ✓ Dedicated account manager
- ✓ Custom onboarding session
Common questions
Ready to calculate with confidence?
Join engineers who design faster, avoid rework, and produce submittals that pass review the first time.
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