1. Official Slack desktop app
RAM: 400 MB–2 GB+ | Open source: No | Platforms: Windows, macOS, Linux
The official Slack desktop app is feature-complete. Video calls, Huddles, Canvas, app integrations, workflows — all of it. If you depend on those features, this is still the only option.
The drawback is resource consumption. On hardware with 8 GB of RAM or less, the Slack PC client's footprint is noticeably painful, especially with multiple workspaces open. The reason is architectural and won't change anytime soon.
Best for: Users who need full feature parity and have reasonably modern hardware.
2. Slack in a browser
RAM: 120–250 MB | Open source: No | Platforms: Any OS with a browser
Open app.slack.com in Chrome, Firefox, or Safari. You get almost the full Slack interface without running a second copy of Chromium on your system. Memory savings are significant — typically 250–400 MB per workspace compared to the Slack desktop app.
Gaps: no system tray, notifications are less reliable, slack:// deep links don't work. For secondary workspaces, these rarely matter. For a primary workspace where you need notifications while your computer is idle, the gaps show.
Best for: Secondary workspaces, or anyone with limited RAM who doesn't need system-level notifications.
3. Franz / Ferdi / Rambox
RAM: 300–600 MB | Open source: Ferdium only | Platforms: Windows, macOS, Linux
These apps bundle multiple communication services — Slack, WhatsApp, Gmail, and others — into a single window. Useful for reducing window clutter if you use many tools.
The important caveat: they're also Electron apps. You're not reducing memory usage compared to the official Slack desktop client; you're consolidating everything into one heavy window. The benefit is organization, not performance. As Slack alternatives in 2026 go, these trade one resource problem for another.
Best for: Users managing many communication services who want a unified inbox rather than lower resource use.
4. Terminal clients (wee-slack, slack-term)
RAM: Under 30 MB | Open source: Yes | Platforms: Any system with a terminal
Terminal-based Slack desktop clients have extremely low memory usage. The tradeoffs are severe: no images, no file previews, limited or no emoji rendering, no voice or video. Setup requires technical comfort with the command line and Slack's legacy API tokens.
Best for: Developers or sysadmins who live in the terminal and primarily need text messaging — a very narrow use case.
5. msga — a native Slack desktop client
RAM: 60–80 MB | Open source: Yes (GPL-3.0) | Platforms: Linux now, Windows & macOS coming
msga is a native Slack desktop client and one of the most compelling Slack alternatives in 2026 for resource-conscious users — not an Electron wrapper, not a browser tab. Built with Qt6 (the same framework used by Telegram Desktop), it connects directly to Slack's API and runs as a real desktop application.
At startup: ~60 MB. At idle: ~0% CPU. The fan stays quiet. The battery lasts longer. Covered features include messaging, channels, DMs, threads, search, file sharing, and emoji reactions. Voice/video and some advanced features are on the roadmap.
Best for: Anyone who primarily uses Slack for messaging and wants the best Slack desktop app experience without the resource overhead.
Comparison table
| Client | RAM | Open source | Native UI | Full features |
|---|---|---|---|---|
| Official Slack | 400 MB–2 GB | No | No | Yes |
| Browser tab | 120–250 MB | — | No | ~90% |
| Franz / Ferdi | 300–600 MB | Partial | No | ~90% |
| Terminal clients | <30 MB | Yes | Yes | ~30% |
| msga | 60–80 MB | Yes | Yes | Core features |