epanet-js

Download- -windows X-lite- Optimum 10 Pro V5.is... Work

No installs. No forced cloud storage. Just fast, local-first water modeling — powered by the engine you already trust.

Launch epanet-js. No login needed.Book a demo

The EPANET user's dilemma

  • Classic EPANET is powerful — but clunky and outdated. Workarounds become your workflow — slow and cumbersome.
  • Big-name platforms look polished, but they're overpriced and bloated with features you don't need to analyze your network quickly.
  • Modern browser-based tools exist — but they force your data into the cloud, raising privacy and compliance concerns. Plus, they offer little for those doing long-term planning and analysis.

You shouldn't have to choose between speed, security, and affordability just to understand your water networks.

Old EPANET UI
Complex Modeling App

Download- -windows X-lite- Optimum 10 Pro V5.is... Work

Background data collection, error reporting hooks, and Microsoft tracking services are hard-disabled to prioritize privacy and free up CPU cycles.

Windows Defender (often disabled or removed for performance). Telemetry and Error Reporting. Pre-installed "UWP" apps (Candy Crush, Disney+, etc.). OneDrive (usually removed but can be re-added). System Requirements

No. X‑Lite requires a . You must back up your data, wipe the system partition, and install from scratch. There is no upgrade path from a stock Windows installation to X‑Lite.

The desktop includes a specialized "Extras" directory providing one-click installers for a browser (e.g., Chrome or Firefox ), the official Microsoft Store, and configuration toggles for core services like Xbox sign-in and printing. Technical Specifications & Resource Usage Stock Windows 10 Pro (22H2) Windows X-Lite Optimum 10 Pro v5 Base Architecture Idle RAM Usage ~1.9 GB – 2.5 GB ~400 MB – 600 MB Initial Storage Footprint Default Background Processes Windows Defender Enabled (Hardcoded) Optional Toggle (Enabled/Disabled) Windows Updates Automatic (Mandatory) Paused / Manual Control Important Installation Notes Download- -Windows X-Lite- Optimum 10 Pro v5.is...

Download Windows X-Lite Optimum 10 Pro v5.iso: Next-Level Performance for Aging PCs

For the first time in years, Jax felt like he actually owned his hardware. No forced updates, no "Hey, try Edge!" pop-ups. Just raw, unfiltered power. But as he settled in, a strange, unlisted icon appeared in the system tray—a small, blinking eye. He hovered his mouse over it. A tooltip appeared: “Optimum performance requires... a witness.”

Microsoft Store and Edge are not pre-installed but are easily accessible via shortcuts on the desktop, allowing you to install only what you need. Pre-installed "UWP" apps (Candy Crush, Disney+, etc

Check out the full breakdown and download links on the official Windows X-Lite channel .

While Windows X-Lite Optimum 10 Pro v5 is a powerful tool for optimizing Windows, it's essential to use it responsibly:

, significantly smaller than a standard Windows 10 installation. Resource Efficiency : It is designed to run on as little as 1 GB of RAM , with idle usage reported as low as 336 MB. Privacy & Control Telemetry and Ads disabled to prevent unwanted data collection. Windows Defender is optional X‑Lite requires a

: By reducing background process counts (roughly 57-65 processes vs. standard 168+), it provides higher FPS and lower latency in games. Technical Specifications Windows X-Lite Optimum 10 Pro Standard Windows 10 Pro Idle RAM Usage ~1.5 GB - 2.5 GB Disk Space (Installed) Processes Telemetry UWP Apps Installation & Requirements Windows X Lite - 2024 Best CUSTOM Lightweight Windows OS

Installing this version is straightforward, similar to installing a standard Windows ISO.

Model water networks instantly.

No setup or downloads — just instant access right in your browser.

Start modeling now

EPANET deserves better — and so do you.

EPANET was a gift to the industry — free, open-source water modeling for all. But commercial vendors built on it, locked away improvements, and left the community behind.

epanet-js is our answer: a faster, simpler, affordable water modeling tool that protects your privacy and sustains the open-source future of water modeling.

We're proud to be part of the next chapter — and we're just getting started.

EPA logo
Source code of epanet-js on GitHub

When you support epanet-js, you support EPANET.

When you purchase more features in epanet-js, you're investing in the future of open-source EPANET development.

Our open-source model balances innovation and accessibility:

Anyone can build on our code. The two-year commercial-use delay gives us the incentive to keep pushing forward — and that fuels progress for everyone.

That means when you support us, you support more affordable hydraulic modeling software for the entire community.

Simple, transparent pricing for every kind of modeler.

Choose the plan that works for you

Free

For everyone.$0 /year
  • Web based EPANET model
  • Background maps and satellite
  • Automated Elevations
  • No limits on sizes
  • Community Support
Launch epanet-js now

ProMost popular

For solo modelers and small utilities.$950 /year

Individual named license

Everything in free, and:
  • Scenarios
  • Professional support
  • Custom layers
Coming soon:
  • Cloud storage
  • Point in time restore - 30 days
  • Demand Analysis
Get Pro

Teams

For teams that build together.$2500 /year

Floating shared license

Everything in Pro, and:
  • Priority support
  • Volume discounts
  • Pay by invoice
Coming soon:
  • Team storage
  • Point in time restore - 90 days
  • Sharing of networks
Get Teams

Have questions? or book a call.

Special access for personal and educational use

Available for non-commercial projects, learning, and student work.

Personal

$100/year

For curious minds and personal growth.

Everything in pro, but:
  • Community support only
  • Non-commercial usage
Buy personal access

Education

$0/year

Free for students and teachers.

Everything in pro, but:
  • Community support only
  • Non-commercial usage
Use your school email account

Frequently asked questions

Find answers to common questions about epanet-js.

Just open your browser and model.

No install. No login. No cloud required.

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Why we built epanet-js

Luke Butler - Co-founder
Luke ButlerLinkedIn

Co-founder

Sam - Co-founder
Sam Payá LinkedIn

Co-founder

You may not know this, but for decades, the U.S. EPA has given the water industry an extraordinary gift: the free and open-source hydraulic modeling software EPANET. Odds are, if you've used any commercial hydraulic modeling software today, it was built on the EPANET engine.

The problem is, instead of giving back to their open-source roots like other industries do, big-name software vendors took EPANET's open code, built private tools on top of the engine, and then locked those improvements behind patents and proprietary licenses.

Some vendors even pressured the EPA to focus only on the engine — discouraging any effort to improve the interface or user experience for everyone else.

Those vendors now charge you exorbitant prices to use their software while EPANET lags behind — and utilities, engineers, and educators with smaller budgets suffer.

We think this is backwards — and we're on a mission to change it. We're focused on creating a better experience for the entire hydraulic modeling community.

That's why we built epanet-js under an FSL license — because we want to give you an affordable, easy-to-use water modeling option that creates a sustainable future for open-source EPANET development.

Support EPANET by using software that supports it back.

A better future for water modeling.

Simple, quick, and useful right out of the gate — designed to open-and-go.

Launch epanet-js now