Let's Chat vs Spark IM
A side-by-side comparison of two self-hosted team chat options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Let's Chat | Spark IM |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 15 · At risk | 61 · Good |
| Status | Archived | Actively maintained |
| Category | Team Chat | Team Chat |
| License | MIT | Apache-2.0 |
| Language | JavaScript | Java |
| Setup difficulty | Medium | Easy |
| Min. RAM | 256 MB | 256 MB |
| Deployment | docker, bare-metal, source | binary, source |
| GitHub stars | ★ 9,797 | ★ 604 |
| First released | 2014 | 2004 |
| Replaces | Slack, HipChat | Slack, Skype |
What are Let's Chat and Spark IM?
Let's Chat
Let's Chat is a persistent messaging application for small teams, offering chat rooms, file uploads, and history search. It is a lightweight Node.js application backed by MongoDB.
- Persistent chat rooms
- File uploads and image embeds
- Searchable history
- LDAP/Kerberos authentication
Spark IM
Spark is a full-featured, cross-platform XMPP instant messaging client with group chat, file transfer, and strong support for the Openfire server. It is aimed at organizations running their own chat infrastructure.
- XMPP desktop client
- Group chat and file transfer
- Tight Openfire integration
- Cross-platform
Let's Chat vs Spark IM: key differences
The biggest difference is maintenance: Let's Chat's repository is archived and no longer developed, while Spark IM is actively maintained. Let's Chat is written in JavaScript, while Spark IM is built with Java. Licensing differs — MIT for Let's Chat versus Apache-2.0 for Spark IM. Spark IM is the more established project (first released 2004), while Let's Chat arrived in 2014. Let's Chat has the considerably larger community, at 9,797 GitHub stars versus 604. Let's Chat lists first-class Docker deployment; Spark IM does not.
Why pick each one
Choose Let's Chat if…
- Released under the MIT license
- First-class Docker support for quick deployment
- Mature project with 9.8k GitHub stars
- Written in JavaScript
Watch out for
- No longer actively developed
- Dated interface
Choose Spark IM if…
- Released under the Apache-2.0 license
- Easy to set up — beginner-friendly
- Written in Java
- Tiny footprint — runs in 256 MB RAM
Frequently asked questions
Is Let's Chat or Spark IM better?
Neither is universally better. Let's Chat has the larger community, while Spark IM is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are Let's Chat and Spark IM free and open-source?
Yes. Let's Chat is licensed under MIT and Spark IM under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Let's Chat and Spark IM with Docker?
Let's Chat: yes. Spark IM: check the project docs for container support.