At a glance — how these 4 alternatives compare
Our read on each project's adoption, maintenance activity and commercial-use risk, derived from GitHub signals and SPDX license terms rather than star count alone. Sorted by stars. How we score.
| Project | Adoption | Maintenance | Commercial use |
|---|---|---|---|
| ★ 89,210 · Go MPL-2.0 | Flagship | Active | Medium risk Changes to the licensed files themselves must stay open |
| ★ 37,032 · PHP AGPL-3.0 | Flagship | Active | High risk Even a hosted/modified deployment can trigger source release |
| ★ 15,313 · C | Mainstream | Active | High risk Distributing a derived work obliges releasing its source |
| ★ 8,832 · PHP AGPL-3.0 | Mainstream | Active | High risk Even a hosted/modified deployment can trigger source release |
† Licenses marked † were read from the repository's LICENSE file on 2026-09-05 (linked, pinned to the commit we read) because the GitHub API returned no SPDX id for them. Unmarked licenses are the GitHub API's SPDX classification.
The alternatives
syncthing
Open Source Continuous File Synchronization
syncthing/syncthing Updated 2026-10-08 server
☁️ Nextcloud server, a safe home for all your data
nextcloud/server Updated 2026-10-08 Beyond file syncing and sharing, a new way to organize your files with extensible file properties and flexible views
haiwen/seafile Updated 2026-09-18 core
:cloud: ownCloud web server core (Files, DAV, etc.)
owncloud/core Updated 2026-10-06 Editor's take
Yusuke Morinaga · last revisited · star counts quoted in the text (≈) are as of that date; the cards above are refreshed daily
Dropbox means two unrelated things, and the four projects below answer only one of them each.
The reason “open-source Dropbox alternative” lists are so confusing is that Dropbox is two products wearing one icon: a sync engine (keep these files identical across my laptops) and a cloud drive (here is storage in the sky, share a link to this file). Those are different problems with different correct answers, and the four projects below do not all solve the same one. Start by deciding which Dropbox you actually used.
If you used Dropbox as a sync engine → Syncthing. Syncthing has ≈88.3k★ — by far the most in this list — and that popularity is earned for the narrow thing it does. It synchronises folders directly between your devices, peer-to-peer, with no server in the middle holding your files. MPL-2.0 licensed, which is the most worry-free license here for embedding or shipping. The catch is structural, not a flaw: because it is peer-to-peer, there is no cloud copy. If all your devices are off, nothing is reachable, and a “share a link with someone outside my devices” workflow does not exist. People migrate to Syncthing, love it, then discover three weeks later that they actually needed the cloud half — so be honest about which half you used.
If you used Dropbox as a cloud drive with a team → Nextcloud. Nextcloud (≈36.7k★, PHP, AGPL-3.0) is the full replacement: server-side storage, web UI, mobile and desktop clients, sharing links, and a whole app ecosystem bolted on (calendar, contacts, an Office-style editor). It is the closest feature match to Dropbox-for-teams. The honest cost is operational — it is a PHP application with a database, a cache, and a reputation for upgrades that need attention. Budget real ops time. The AGPL license is a non-issue for running it as your own team’s drive.
If Nextcloud’s surface area scares you → Seafile or ownCloud. Seafile (≈15.2k★, C) is the lean pick. Its storage engine is written in C and is genuinely faster than the PHP projects when you have a lot of files — hundreds of thousands of small files is where Seafile pulls ahead and where Nextcloud’s sync can crawl. The GitHub API returns no SPDX id for it; the card shows the GPL-2.0 (with an OpenSSL linking exception) we read in the server repository’s LICENSE. The desktop client and SeaDrive live in separate repositories, so check the licence of each component you ship. ownCloud (≈8.8k★, PHP, AGPL-3.0) is the project Nextcloud forked from years ago; it still ships (see the card’s last-push date) but for most new deployments Nextcloud has the momentum. I would only choose ownCloud if you have an existing ownCloud install you do not want to migrate.
The two things you cannot get back
Dropbox’s smart sync — files visible in your filesystem but streamed on-demand rather than stored locally — has no clean open-source equivalent; the alternatives sync whole files or whole selected folders. And Dropbox Paper, the collaborative doc layer, simply is not part of any of these (Nextcloud’s bundled editor is the nearest, and it is not Paper). If either of those was load-bearing in your workflow, factor in a separate tool for it rather than expecting one of these to cover it.
Comparison notes
Your choice here depends on whether you want sync or storage. Syncthing nails device-to-device synchronization, but it's peer-to-peer — at least one machine has to stay online as a hub, and there's no cloud bucket behind it. If you want something closer to Dropbox proper, Nextcloud self-hosted gives you cloud storage, sharing, collaboration, and mobile apps, at the price of meaningful operational upkeep; Seafile is a leaner take that handles large numbers of files more gracefully. The feature you won't find bundled into any single open-source package is the combination of Dropbox Paper and smart sync's on-demand file streaming.
Migration tips
- Use Dropbox's desktop client to sync all files locally before migrating to your OSS tool
- For Nextcloud migration, run rclone to copy files from Dropbox to Nextcloud without re-downloading everything
- Audit Dropbox Paper documents and export as Markdown or DOCX before migrating — Papers are not files
- Check all shared folder memberships and recreate sharing permissions in your target tool
- Update all connected app integrations (Slack, Zoom, Adobe) that access Dropbox via OAuth
Which alternative should you pick?
Replacing Dropbox isn't a single call — it's a trade between license terms, team size, and how much early-stage roughness you can absorb. The 4 projects above split along those lines:
- You want the project with the most GitHub stars in this list → syncthing. 89,210★ — the most of the 4 projects here. Stars measure attention, not quality or maintenance; check the last-push date and the Editor's take before reading more into it.
- You want a copyleft project whose modifications must be shared back → server. AGPL-3.0 licensed — distributing a modified version (and, under AGPL, offering it over a network) obliges releasing the source, which is what some teams explicitly want.
- You want the project with the most recent push activity → server. Last push 2026-10-08 — the freshest activity in this list.
License & commercial-use notes
When replacing Dropbox, the license usually decides more than the feature list — whether you can modify it, ship it inside a product, or host it as a service. The 4 projects here fall into:
- Weak copyleft (syncthing) — LGPL / MPL — you can use them inside a larger work, but changes to the licensed files themselves must stay open.
- Strong copyleft (seafile) — GPL / EPL — distributing a derived work obliges you to release its source under the same terms. Fine for internal use; plan carefully before proprietary distribution.
- Network copyleft (server, core) — AGPL / SSPL — the copyleft trigger extends to offering the software over a network, so a hosted deployment of a modified version can oblige you to publish your changes. Read the exact terms before building a paid hosted product on these.
License fields come from the GitHub API's SPDX classification and can lag a relicense. Where the API returned no SPDX id, the license marked † was read from the repository's LICENSE file on 2026-09-05; the † links to the exact file and commit we read. The repository linked on each card is authoritative — confirm its LICENSE file before any license-sensitive deployment.
Maintenance health of these 4 projects
Of the 4 projects listed, 4 shipped at least one commit in the last 12 months. See how we rank for the full criteria and our self-hosting cost reality check, which apply across every comparison on this site.
Frequently asked questions
How do these 4 alternatives compare on maintenance health?
4 of 4 have shipped a commit in the last 12 months. At least one project here has 5,000+ GitHub stars. Always check the last-pushed date in the cards above and read the latest closed issues — those two signals are the fastest public check we know of.
How this page was compiled
- Repository facts (stars, license, language, last push) come straight from the GitHub public API and are linked on each card as the primary source. Where the API returned no SPDX id, the licence marked † was read from the repository's
LICENSEfile (linked, pinned to the commit we read, with the date checked). - Editorial analysis (the intro, comparison notes and migration tips) is Claude-drafted from Dropbox's use case and the alternatives' repository metadata — in Claude Code sessions or scheduled routines run under the operator's account. Samples are spot-checked against the upstream repositories; entries are not individually reviewed unless they carry a signature. See what Claude drafts and what the operator writes.
- Editor's take is signed by Yusuke Morinaga. It was drafted in a Claude Code session the operator ran, then read and confirmed by Yusuke Morinaga before publication, and carries the date it was last revised. It is written from each project's README, LICENSE, release history and issue tracker — not from running the project in production; where that distinction matters, the take says so.
- Maintenance signal: 4 of 4 projects shipped a commit in the last 12 months as of the latest rebuild (most recent activity: ).
- Last editorial review: by Yusuke Morinaga.
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