Built for communities but a capable team-chat tool. Discord Free is free forever with unlimited servers, channels, full message history (no time cap), voice & video calls, screen share up to 1080p@60fps, and 25 MB file uploads; Nitro (~$9.99/mo) adds HD streaming, 500 MB uploads, and custom emoji.
Visit site ↗Open-source (AGPLv3) self-hostable Slack alternative. Free to self-host with unlimited teams, channels, full message history, file sharing, and integrations; Mattermost Cloud offers a free tier for small teams, and paid Professional from ~$10/user/mo adds enterprise compliance, SSO, and analytics.
Visit site ↗An async-first team-chat tool from Doist (makers of Todoist) built around threaded conversations instead of real-time channels. Twist Free is free forever for teams of up to 5 members with 1 month of message history and 5 GB file storage; paid Unlimited from ~$6/user/mo adds unlimited members, full message history, and unlimited integrations.
Visit site ↗The default workplace chat. Slack Free is free forever with message & file history capped at 90 days (changed from the old 10k-message limit in Aug 2024), up to 10 app integrations, 5 GB total file storage, 1:1 and group audio/video huddles, and unlimited channels; paid Pro from ~$7/user/mo adds unlimited history, unlimited integrations, and Slack Connect.
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