We will talk today about open source prototyping tools.

The open source ecosystem is continuously improving. Many years ago we didn’t have specialized apps for engineering, banking, accounting, designing or other type of use cases, but now we do. Each day, new developers are starting to introduce more niche apps for the open source app catalog.

In the case of UX and UI designers, open source alternatives are extremely important because:

  • Cost: Using a proprietary UI/UX prototyping tool could be too costly on the long run, especially if it was one of Adobe’s products where you have to get a monthly subscription or otherwise lose your access.
  • Collaboration: Have a missing feature in mind for that open source software? You can either request it from the developers or create it yourself, if you know how to code.
  • Vendor Lock-in: Since everything is open source, all your data and files are yours. You don’t have to worry about uploading your work on someone else’s servers or be in fear of losing it.

In our article today, we’ll introduce the 5 open source prototyping tools than you can depend on to do your UI/UX work.

Open Source Prototyping Tools

1. Pencil

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Image via pencil website

Pencil is the most feature-rich and well-known open source prototyping tool that you may hear of. It comes with a very functional and clean GUI to design the UI sketches you may need, and works on all major platforms (Windows, macOS and Linux). The latest release of it was released just around 6 months ago, and its initial development looks like it was started back in 2012.

The program has built-in shapes, icons and other ready types of objects that you can use to supplement your sketches. It also has a built-in browser for grabbing these “collections” from the community for extra addons or from OpenClipArt.org when needed.

You can use Pencil to create user interfaces along diagrams, and each element in your sketch can be “linked” to other pages when clicked.

Pencil is licensed under the GPL 2.0 license.

You can go ahead in downloading Pencil for Windows, macOS and Linux. Or learn more about it from its official website.

2. Alva

open source prototyping tool 7

Alva is another open source prototyping tool in this list. Its development started in 2017, and works currently on all the major operating systems too (Windows, macOS and Linux). Alva’s user interface is quite modern and stylish comparing to other software in this list.

Alva looks like it is focusing more on simpler user interface and a straightforward workflow for creating UI/UX sketches. It is quite easy to learn and use, and supports a number of ready UI components to use by default. If you are missing a specific component in your mind, then you can create it yourself thanks to the documentation they have prepared.

Alva is licensed under the MIT license, and written in Node.js.

You can download Alva is an already-prepared package for your Linux distribution, or other different operating systems from here.

3. Quant-UX

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Unlike the other software in this list, Quant-UX is a web-based service; Meaning that there’s no software for you to download and install. Instead, you just use the online service to design and save the prototype you wants.

It is still free (Both as in “free coffee” and as in “freedom), but it being a web service could be a double-edged sword:

  • One one hand, you don’t need to install anything on your device. You can just open the website from any web browser and start working.
  • On another hand, you are restricted to use the website and can not fully put your hands on your data and connections, unless you go in deploying your own instance of the software on your own servers.

However, Quant-UX is a really advanced open source prototyping tool. It supports widgets from multiple famous UI kits, and you can import additional ones from any URL you want. Also, you can link your screens based on a programmatic logic, or directly export them as PNG images once you are done.

To try Quant-UX, visit its official web address. You can view its source code on GitHub.

4. Penpot

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Penpot is an upcoming open source prototyping tool. It isn’t fully developed and stable yet (Still currently in beta), but it is an amazing project to keep an eye upon.

Its developers aim to make it fully SVG-powered, meaning that each component you use in your UI sketches is coming from an SVG file, or can be exported to an SVG file. This is especially good in case you want to deploy your website or UI as it is using the SVG supported technologies too. In this way, both your UI editor and your actual designs will be fully open source.

Penpot developers plan it to be completely open source and free of charge. They have an online platform of the app thay you can use right now too: https://design.penpot.app/

It is also worthy to note that Penpot was previously called UXBOX, but the team changed its name few months ago.

You can track the development progress from the project’s repository on GitHub, or try to participate in the development right now. You can also follow their Twitter account.

5. Akira

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Another yet-in-development UI designing tool is Akira.

Akira – unlike the other options in this list – targets the Linux desktop specifically. It is written in both the Vala programming language and the GTK toolkit.

No ready versions are available of Akira at the moment (Just the unfinished source code), but you can keep an eye on their GitHub page or other links to follow their progress. The software is available to install as a Flatpak package only.

The Bottom Line

So you have seen the current available open source UI/UX designing tools so far. As you can see some of them are still under heavy development, so this sector in open source is still being gradually built over time.

If you know any other open source prototyping tool that we forgot to mention in our list, please tell us about them in a comment below.

Useful Services & Offers

Check the following list of services and tools we use in our day-to-day work, perhaps they can be beneficial to you:


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Saisurya Kattamuri

Please include new tool called AkiraUX


Please include new tool called Penpot


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