Comparison

Cotton vs Seafile: browser polish versus old-guard desktop sync.

Seafile is sync-and-library first — the desktop client is the primary path. Cotton is browser-first, with the same chunked engine under WebDAV and the native upload. This is not a scoreboard with fake certainty; it is a product-fit comparison for self-hosted file cloud decisions.

Seafile alternativeSelf-hosted file cloudStorage engineDocker deployment

Both have content-addressed dedup. The difference is everything around it.

Seafile pioneered chunked + content-addressed storage in self-hosted clouds, and Cotton uses the same fundamental idea. The gap is in the surface around it: Cotton ships audio waveforms with cover art, an STL/OBJ/3MF 3D viewer, mobile PDF with selectable text, HEIC preview, realtime SignalR sync between clients, and auto-restore from its own backup. Seafile ships none of these in the browser. The engine is great; the showroom is empty.

Both: SHA-256 chunks, dedup across the instance.
Cotton only: audio waveform + LRC lyrics, STL/OBJ/3MF, mobile PDF text layer, HEIC, realtime sync.
Cotton only: auto-restore DB from own protected backup.

Libraries are mandatory in Seafile. Folders are not.

Seafile's data model is libraries-first — you cannot just open a folder. You first choose which library, then navigate. Cotton uses a free folder structure: you open the root and it is yours, like a real filesystem. Encrypted libraries in Seafile are all-or-nothing per library; Cotton encrypts every chunk by default, and lets you add client-side E2E on selected folders.

Sync behavior

Seafile's old-guard desktop clients have years of production deployments behind them. Cotton ships a native Android app and a Cotton Sync desktop client for Windows and Linux, alongside WebDAV and a PWA. If a long-running desktop sync stack with that much mileage is your primary path, Seafile is the established pick.

WebDAV: Cotton is faster

Seafile's WebDAV is mid-tier in throughput. Cotton's WebDAV PUT runs through the same chunked pipeline as the native client, so large files do not slow down on the protocol path.

Fiddly to stand up, dated in the browser

Seafile's self-hosted setup is command-line driven and reviewers often describe it as fiddly, and many find its browser UI dated next to a modern file cloud (Seafile is reworking it in v12). Cotton is one Docker image plus Postgres, and the modern browser surface is the whole point.

Encryption is per-library, all or nothing

Seafile's encryption is per-library and all-or-nothing - you encrypt a whole library or you don't, with no per-folder choice - and several capabilities sit behind the paid Pro edition. Cotton encrypts every chunk by default and adds client-side E2E on the folders you pick.

Pick Cotton for browser file UX. Pick Seafile for desktop sync.

If you live in the browser file surface and want it to feel like 2026 — audio that browses, 3D that renders, video that seeks on encrypted storage, snapshots that roll back instantly — Cotton is the call. If you live in the desktop sync client and the browser is a fallback, Seafile is the old-guard pick.

Decision matrix

Where the tradeoff actually sits.

Cotton does not need to beat every long-established ecosystem on every surface. The useful comparison is narrower: storage behavior, privacy posture, recovery model, deployment shape, and product focus.

Area

Cotton

Seafile

Product lane

Preview-rich file cloud with storage proof surfaced in the browser.

Sync/library-first file product with old-guard client workflows.

Browser UX

PDF, audio, video, text, Markdown, images, shares, and 3D previews are core product surface.

Strong sync/share workflows; browser file UX is a different priority.

Storage model

Content-addressed chunks, manifests, snapshots, and WebDAV through one storage path.

Established sync architecture and libraries can be the stronger reason to choose it.

Operations

Security checkup, database integrity, backups, and deployment clarity are part of the pitch.

Operational fit depends on existing Seafile experience and client expectations.

Content addressing

Cotton stores file content as chunks and manifests, so deduplication, verification, versions, snapshots, and cleanup share one mental model.

Streaming safety path

Compression and AES-GCM encryption sit in the normal storage path; the site does not sell isolated crypto speed as user-visible ingest speed.

Recovery by references

Snapshots, versions, trash, and reclaim are positioned as ordinary file-cloud workflows, not emergency-only backend chores.

Focused runtime

Cotton deliberately stays narrower than broad collaboration suites: files, previews, sharing, WebDAV, recovery, and operator visibility.

Cotton lane

Pick Cotton for a storage-first file cloud.

Cotton is the cleaner story when files, previews, shares, snapshots, versions, WebDAV, passkeys, admin diagnostics, and a compact Docker/Postgres deployment are the main problem.

Seafile lane

Pick Seafile when its broader lane is the point.

Operators who primarily want old-guard sync behavior and are happy with Seafile's model.

Choose Cotton when

You want a focused self-hosted file cloud with content-addressed storage, streaming crypto, snapshots, previews, WebDAV, sharing, passkeys, and a compact Docker deployment.

Choose Seafile when

You need long-running sync/share workflows, old-guard clients, custom file properties, and file views more than the Cotton storage-engine and recovery-model strengths.

Positioning

Cotton is not trying to be a bigger suite than Seafile. It is trying to be the sharper file cloud when the file engine itself is the product decision.

Still choose carefully

If the priority is a modern content-addressed storage engine with previews, snapshots, WebDAV, and deployment clarity in one focused product, Cotton is easier to explain.

Storage model Benchmarks Security

Last reviewed June 2026. Every line below links to its receipt - the actual issue, doc, or commit it came from. Competitors move fast; if a link goes stale, open an issue and we fix it.

Receipts

FAQ

Direct answers

Is Cotton a drop-in replacement for Seafile?

Not always. Cotton is a focused file cloud, not a clone of every app and integration in the older ecosystems. It fits best when file storage, previews, sharing, snapshots, WebDAV, security, and deployment simplicity are the main problem.

Why compare Cotton to established products?

Because people searching for a self-hosted file cloud often start with the familiar names. The comparison makes the tradeoff explicit instead of pretending every product has the same goal.

When should I still choose Seafile?

If you want old-guard sync clients above everything else, Seafile is still the default call. The desktop clients have years of mileage on them. The file browser UX in the browser is more mechanical than Cotton's.