Chafa Frontend

boomboompower — Wed, 11 Jun 2025 19:49:39 +0000

I Built a Web UI for Chafa So You Don’t Have to Touch the Terminal (Unless You Want To)

A few months ago, I came across Chafa — a command-line tool that turns images into ANSI/ASCII art. If you’ve never tried it, it’s kind of brilliant. You point it at a PNG or JPEG, and it spits out a wall of colored text that looks eerily close to the original image — all using braille, Unicode blocks, or ASCII characters.

Naturally, I did what any curious dev would do:

I fed it a few pictures, sat back, and watched my terminal become an art gallery.

But then I had a thought:

What if you didn’t have to install anything? What if you could just drop an image into your browser and get the same result — instantly?

That’s how this started.

Introducing: Chafa Frontend

This is a minimal web app that wraps the Chafa CLI in a Flask server and adds a browser-based UI on top.

No terminal. No CLI flags. Just upload → configure → render.

👉 GitHub Repo

I didn’t write the magic — Chafa does all the heavy lifting in the project. Ironally, most of the code in this repo is for getting material design working, or even just validation. All-in-all, this project just tries to make Chafa more accessible.

Why Build a Web UI for a CLI Tool?

Honestly? Because I wanted to use Chafa on a phone.

And I wanted to share ASCII with my friends who have never opened a terminal in their lives.

Also: I think good CLI tools deserve good UIs. Not because the CLI is lacking, but because a tool can be powerful and approachable at the same time.

How It Works

The frontend is a simple single-page app using Material Design 3 components — just enough UI to pick a file, select some Chafa options, and display the result. No frameworks, no build steps — just HTML/CSS/JS.

The backend is a lightweight Flask server. When you upload an image, here’s what happens:

The image and selected options are sent to the backend.
The backend validates the inputs, saves the image temporarily.
It invokes chafa with the requested options.
The ANSI output is returned to the frontend and rendered in the browser using ansi_up.

Why Material Design 3?

No big reason — I just liked the idea of giving a CLI tool a polished, mobile-friendly interface. Material Web Components made it easy to prototype quickly and still look decent across devices. Mainly, I wanted to play around with some of the latest standards for material design - as most of my current projects have been using Material Design 2 components of some kind.

Lessons Learned

Building for “non-technical users” forces you to think carefully about defaults and feedback.
Even tools designed for terminals can benefit from a little UX thinking.
Chafa is extremely fast. I never had to optimize anything — it just works.
Material Design 3 (at least when working purely in DOM), feels like it has a long way to go. I read through the documentation looking for formatting, and was puzzled when the components wouldn't style properly. Once I read through the source code there were frequent mismatches which was a shame.

Final Thoughts

This isn’t a reinvention of image-to-ASCII conversion — that credit goes entirely to Chafa and Hans Petter Jansson. This is just a small wrapper to make it more usable in a browser context.

If you’re into terminal aesthetics, retro graphics, or building useful frontends around powerful backends — check it out! If you have any suggestions or extensions, feel free to let me know or fork it 🙂

👉 Check it out

DEV Community: boomboompower