Free MEP Calculators & Engineering Guides
Standard-based Electrical, HVAC, Plumbing and Fire & Safety calculators. Every one explains its formula, shows a worked example and common mistakes, and lets you download the result as a PDF.
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Pick your field and jump straight to the related tools and guides.
Featured Calculators
Every free calculator, organised by discipline. Pick a title to open it.
Electrical
5HVAC
4Fire & Safety
6Plumbing
8How It Works
From question to result in three simple steps.
Pick a calculator
Search by name or browse by discipline. Each tool states the standard it is based on.
Enter your values
Fill in your project inputs. Nothing is pre-filled, so you never reuse a wrong number by mistake.
Get the result and PDF
See the result instantly, read the formula and worked example, and download a PDF for your notes.
Why Engineers Use MEP Analysis
Simple, transparent tools. No black boxes.
See the formula
Every calculator explains how the answer is calculated, with a worked example.
PDF result
Download your result as a PDF in one click, ready to add to your calculation notes.
Works anywhere
Use it on a phone at site or on a laptop in the office. No app to install.
Free, no signup
No account, no paywall. Open a calculator and start.
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About MEP Analysis
MEP Analysis is a free engineering resource for Mechanical, Electrical and Plumbing professionals, students and site engineers. The goal is simple: give you fast, reliable calculators and clear guides, so you can check a design, understand the method and get on with your work.
Every calculator on this site comes with a short explanation of the formula, a worked example and a list of common mistakes. That way you do not just copy a number, you understand where it comes from. Where a standard applies, such as NEC, IS or ASHRAE, it is listed on the calculator card.
Results are meant for estimation and learning. Always verify final designs against the applicable code and with a qualified engineer. You can read the full Disclaimer for details.
Frequently Asked Questions
Quick answers about the calculators.
Are the calculators really free?
Yes. All calculators are free to use and do not need a signup or login.
Which standards do the calculators follow?
It depends on the calculator. Commonly used standards such as NEC, IS and ASHRAE are used, and the standard for each tool is shown on its card and its page.
Can I use the results for final design or construction?
The results are for estimation and learning. Please verify them against the applicable code and with a licensed or qualified engineer before final design or construction. See our Disclaimer for details.
How does this site handle my data?
Calculations run in your browser. For details about cookies and analytics, please read our Privacy Policy.
Ready to check your design?
Open a calculator, enter your values and get a clear, explained result.
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