Free Slack Alternative: Diode Collab Keeps Your Whole Chat History
October 26, 2026 | Category: Diode
Free Slack Alternative: Diode Collab Keeps Your Whole Chat History
People searching for a free Slack alternative are usually trying to get past Slack’s free-plan limits. On that plan you can view and search messages and files from the last 90 days. Slack hides anything older, and it permanently deletes messages and files more than one year old. You can install up to 10 apps, and huddles are one-to-one only. Diode Collab is private team collaboration — messaging, files, and ZTNA-style secure access — organized in Zones. A new Zone starts on the free Nomad plan. The docs describe unlimited chat history on every plan, keys on the devices in the Zone, and no chat, files, accounts, or personal information stored on a Diode vendor server.
What Slack’s free plan limits today
Slack’s pricing comparison lists Free at $0. Message and file history is a 90-day limit. Integrations are capped at 10. Huddles are 1:1 only. Slack Connect, for people outside the company, is 1:1 only. Data retention is up to 1 year. A free account gets 1 workspace. The directory holds over 2,600 apps; Free can install ten of them.
Usage limits for free workspaces says you can view and search the last 90 days of messages and files (clips, documents, images, and audio or video included). Older items are hidden, and anything past one year is permanently deleted. Owners may instead delete at 90 days, which also deletes what the visibility limit has already hidden. From August 26, 2024, data older than one year may be deleted on a rolling basis. At 10 apps you uninstall one to add another. A separate high-volume limit may block a burst of messages or files; Slack does not publish a number for it.
Feature limitations on the free version limits a downgraded workspace to one-on-one huddles in direct messages. Group huddles are paid. Slack plans and features repeats the 90-day window, the one-year deletion, one-to-one huddles, and the 10-app cap. A paid plan removes the message, file, and app limits, so “free Slack, with the archive” is a subscription.
Slack encrypts data in transit and at rest on its own systems. That is not end-to-end encryption: Slack can process workspace content so search, retention, exports, and apps function. See Is Slack end-to-end encrypted? and Can Slack read my messages?.
What Diode Collab is
Collab is for a private team, project, or household: messaging, files, and a path to selected internal tools. People work in Zones, shared security perimeters rather than Slack workspaces.
Keys stay on devices. Each device holds an encrypted-on-disk key for the account. Chat and files are end-to-end encrypted among Zone members. External web links use HTTPS, which Pricing and plans states explicitly.
Diode does not hold the archive. Collab is local-first. Chat content, files, accounts, and personal information are not stored on a Diode vendor server. History lasts while the Zone’s devices still have it. If every device that held the Zone is lost, the history goes with them. See Self-custody Slack alternative.
Membership is a proof, not a phone number. The About page says no message or file data goes on-chain, only proofs of membership, meant to stay opaque outside the Zone. Sign-up does not ask for a phone number or an email address. Identity is a username plus device keys. That suits a team that does not want a vendor identity file, and it is a poor fit when single sign-on must be the front door. See Encrypted Slack alternative.
ZTNA-style access — tunnels to internal tools, rather than a separate VPN concentrator — is a product capability. On /pricing/, secure equipment access, regional access tunnels, and custom endpoints are Business features. Nomad does not include them.
Nomad, the free plan
The cards on /pricing/ are Group, Team, and Business. There is no $0 card. “All plans include” links to What can I do with the Free Version? and lists end-to-end encryption for messages, files, and browsing; group and direct messages; file sharing; a secure markdown editor; browser upload and download; unlimited storage; and unlimited users.
The FAQ says Collab is a free app: a theoretically unlimited number of free Zones, with unlimited users, at no cost. Free Zones are for individuals, families, communities, and ecosystems, and the page credits the Diode Foundation and the Moonbeam Network. If you want certain features in a Zone, or you are using Diode as an organization or for commercial purposes, you put that Zone on a paid plan.
Pricing and Plans names the default. A new Zone starts on Nomad. Every plan gets group and direct chat, file collaboration, asset connectivity, markdown editing, link sharing, as much storage as your devices can handle (“Unlimited Storage”), and unlimited chat history. Paid plans bill per user. People in the “In Moderation” role are not billed.
Secure File Sharing is narrower: Nomad shares across your linked devices, suited to passwords, notes, and personal information. On Group, admins upload and members can use files but cannot add them. Team and above is full file-sync control. Neither page publishes a Nomad channel cap. The channel and web-link counts below are Group’s. History on Nomad is the copy on member devices, so a lost laptop or a departure that takes the last copy is something the team has to plan for.
What the paid plans cost
From the pricing page. Cards show the monthly price. Yearly rates and annual amounts are in the same page source.
| Plan | Covers | Monthly per user | Yearly rate | Annual amount |
|---|---|---|---|---|
| Group | Messaging | $3 | $2.50 | $30 |
| Team | Messaging and files | $10 | $8.50 | $100 |
| Business | Messaging, files, and remote access | $15 | $12.50 | $150 |
Group lists private invitation codes, new-user moderation, an admin role, private chat channels, private drives, a chat visibility policy, 10 chat channels, 10 web links, and standard support. Team adds member file collaboration, a file sync policy, file backup, team markdown docs, and 20 web links. Business adds secure equipment access, regional access tunnels, custom endpoints, 100 chat channels, and 100 web links.
Confirm the live figures on /pricing/. Use a paid plan for organizational or commercial use, and for the admin, file, or tunnel features above.
Free tiers, from each vendor’s pages
If a vendor does not state a history cap, the cell says so.
| Free option | History | Other stated limit | Who runs it |
|---|---|---|---|
| Slack Free (pricing, limits) | Last 90 days visible. Older than one year is deleted. | 10 apps. Huddles and Slack Connect are 1:1. One workspace. | Slack |
| Mattermost Entry (editions) | 10,000 channel messages stay searchable. Older messages stay in the database and are hidden. | Aimed at teams under 50. Community support. No compliance export, legal hold, or high availability. | You, on your server |
| Element Server Suite Community (pricing) | No history cap on that page. | Free, AGPL, includes Element Call, 1–100 users. Community Synapse is not for production. | You, on your server |
| Rocket.Chat Starter (plans) | Searchable history. No day cap stated. | $0, up to 50 users. No air-gapped deployment. No paid support. | You, on your server |
| Rocket.Chat Community (same doc) | No day cap stated. | MIT license, 100 concurrent users, 10,000 pushes a month. Not for production you depend on. | You, on your server |
| Discord (search, caps) | Kept until you delete them, or someone with Manage Messages does. Search reaches the first message. | 10 MB uploads. 100 servers. 5,000 search results. | Discord |
| Diode Collab Nomad (FAQ, plans) | Unlimited history on every plan, on the Zone’s devices. | Theoretically unlimited free Zones and users. Storage is what those devices hold. | Local-first. No chat, files, accounts, or PII on a Diode server. |
Mattermost marks further Entry limits — boards, playbooks, call length, push volume, agent queries — as future, so they are not listed as current caps. Team Edition is separate: MIT-licensed, under 250 users, no single sign-on.
When Slack is still the right product
Slack wins when the company already works there and the workspace is the integration hub.
The directory is the gap. Ten apps is a real free-plan limit, and the paid catalog of over 2,600 apps has no Collab equivalent. Jira, GitHub, a CRM, or a bot in a channel is a job Collab does not try to do. Workflow Builder sits on paid Slack because the service can see the workspace and act on it.
Administration is the other gap. Slack’s grid reserves SAML single sign-on, SCIM, data-loss prevention, legal holds, full-message exports, audit logs, and a HIPAA-oriented configuration for paid and enterprise plans, because Slack holds the data. Exporting a channel, placing a hold, or deprovisioning people from an identity provider is a higher Slack plan’s job. Channels and threads are also what most companies already teach.
Collab fits when the history and the keys should stay with the team, without a vendor-readable archive in exchange for the directory. See Encrypted Slack alternative.
When Mattermost, Element, Rocket.Chat, or Discord wins
Mattermost wins when you want to run the server. Entry is free, capped at 10,000 visible messages, for small teams. You take on patching, backups, and a database that still holds messages Entry will not show. Running that server does not leave keys only on member devices.
Element wins for Matrix federation or a homeserver you or a host runs. Community is free under the AGPL, includes Element Call, and is listed for 1–100 users. Element says Community Synapse is not for production, and that encryption is on by default unless a room is left unencrypted. The homeserver still handles accounts, routing, and media. See Diode Collab vs Element.
Rocket.Chat wins when you want a server you deploy, with marketplace apps, inside Starter’s 50 users or Community’s limits. Starter has searchable history and single sign-on, without air-gapped deployment or paid support. Community is the MIT edition: 100 concurrent users, 10,000 pushes a month, and not for production you depend on. See Diode Collab vs Rocket.Chat.
Discord wins for public communities, voice, screen sharing, and bots. Messages stay until a person deletes them. Base uploads are 10 MB. It is a centralized community product, a poor default when the vendor should not hold the chat. See a secure Discord alternative. For a commercial encrypted messenger, see Diode Collab vs Wire.
Nomad will not give you a 2,600-app directory, eDiscovery, SCIM, or group huddles, and it will not restore a channel after every laptop is wiped. Encryption does not cover an unlocked stolen laptop or a file copied into another tool. Keep more than one device in the Zone if a lost laptop must not take the history with it. This post makes no ISO, SOC 2, HIPAA, or GDPR certification claims.
Frequently asked questions
Does a free Slack alternative keep the whole history?
Slack’s free plan shows 90 days and deletes content after a year. Nomad keeps unlimited history on the Zone’s devices. Mattermost Entry shows 10,000 channel messages. Discord keeps messages until a person deletes them. Element Community and Rocket.Chat Starter state no day cap; you run the server that stores the history.
What does Nomad include?
New Zones start there: theoretically unlimited Zones and users, at no cost, for individuals, families, communities, and ecosystems. The pricing page’s shared list covers encryption, chat, file sharing, markdown, browser upload and download, unlimited storage, and unlimited users. The plans doc adds unlimited chat history on device storage. Commercial use and extra features take a paid plan. The file-sharing doc describes Nomad as sync across your own devices.
Does Diode store the chat?
No chat content, files, accounts, or personal information on a Diode vendor server. Keys stay on member devices. The blockchain holds membership proofs, not messages. Share links use HTTPS. The history still depends on the devices in the Zone.
When should we stay on Slack, or run a server ourselves?
Stay on Slack when you need the app directory, or paid Slack’s group huddles, full archive, single sign-on, or eDiscovery. Run Mattermost, Element Server Suite Community, or Rocket.Chat when you want to operate the chat server. Collab is a local-first app in Zones, and it does not replace Slack’s bots or admin APIs.
What do paid plans cost?
Group $3, Team $10, and Business $15 per user per month. The page source also lists yearly rates of $2.50, $8.50, and $12.50, and annual amounts of $30, $100, and $150. In Moderation users are not billed. Confirm /pricing/ before you buy.
Start on Nomad
Create a Zone and it starts on Nomad, with the history on your devices. Upgrade when you need Group, Team, or Business features.