Best open-source alternatives to Dropbox

Immich is a self-hosted photo and video management system designed for people who want their media library stored and accessed on their own infrastructure. It provides a mobile and web experience for uploading, browsing, backing up, and organizing photos and videos, with support for features like metadata search, albums, sharing, and facial recognition. The project is aimed at users who want a high-performance alternative to cloud photo services while retaining control over their data. The README also highlights administrative user management, OAuth support, public and partner sharing, and offline support in the mobile app, indicating that it serves both individual households and multi-user deployments.

Syncthing is a peer-to-peer file synchronization tool designed to keep files consistent across multiple computers without relying on a central cloud service. The README emphasizes safety, security, ease of use, and automatic operation, positioning the project for individual users who want reliable syncing with minimal manual intervention. The project provides guidance for getting started, building from source, and running in Docker, and it references GUI wrappers for Windows, macOS, and Linux. It also points users to a dedicated documentation site, a forum, and a GitHub issue tracker for support and bug reports. The software is released under the MPLv2 license and includes signed release binaries, with an automatic upgrade mechanism mentioned in the README.

Cloudreve is a self-hosted file management system designed for people or organizations that want to run their own cloud-style file platform. It focuses on managing files across multiple storage backends, including local storage, remote nodes, and several third-party object storage providers. The project provides a web-based interface with features for uploading, downloading, previewing, sharing, and organizing files. It also supports multi-user operation, WebDAV access, background downloads through Aria2/qBittorrent, and rich online preview/editing for common file types. The README positions it as an all-in-one package for both quick local testing and production deployment.

SeaweedFS is a distributed storage system aimed at handling very large numbers of files efficiently. It is positioned for users who need scalable storage with low-latency access, including S3-compatible object storage, file storage, and lakehouse-style tables on top of the same underlying data. The README describes several deployment paths, including a single-binary quick start, Docker, Docker Compose, Helm on Kubernetes, and building from source. It emphasizes a stateless S3/filer layer, scalable volume servers, and support for replication, erasure coding, tiered storage, and cloud caching. It also highlights an API surface that is broad enough to work with common tools such as AWS SDKs, rclone, restic, Spark, and Trino.

Puter is an open-source internet operating system designed as a personal cloud and application platform. It is aimed at people who want a self-hostable, privacy-oriented place to store files, apps, and games, as well as teams or developers building and publishing web applications and games. The project presents itself as an alternative to mainstream cloud storage services while also offering a remote desktop-style environment for servers and workstations. The README highlights a hosted version at Puter.com, but it also provides local development and self-hosting instructions using either a direct Docker run or Docker Compose setup. The software requires Node.js and npm for local execution, and the repository is licensed under AGPL-3.0.

copyparty is a self-hosted file server aimed at turning nearly any device into a shareable storage endpoint. It is designed for people who want simple uploads and downloads from a browser, but it also exposes traditional transfer protocols such as WebDAV, SFTP, FTP, TFTP, and SMB/CIFS for clients that prefer them. The project appears geared toward personal servers, small deployments, and power users who want flexible access methods and fine-grained control over folders, permissions, and sharing. Its README highlights browser-based file management, temporary share links, thumbnails, search, media playback, and other convenience features, while emphasizing that the server itself only requires Python and that most dependencies are optional.

restic is a command-line backup program designed for users who need reliable, secure, and efficient backups across Linux, macOS, Windows, and several BSD variants. It emphasizes ease of use, speed, verifiability, security, and storage efficiency, making it suitable for both individual users and administrators who want a straightforward backup tool that can be restored when needed. The project works by creating a repository, then storing backups as snapshots that can later be restored or mounted for browsing. It supports a variety of native backends, including local directories, SFTP over SSH, an HTTP REST server, Amazon S3, OpenStack Swift, Backblaze B2, Azure Blob Storage, Google Cloud Storage, and additional services via rclone. The README also points users to online documentation and a forum for support.

OnionShare is an open source application designed for private, anonymous communication over the Tor network. It is aimed at people who want to share files securely, temporarily host a website, or chat without relying on a centralized service. The project provides platform-specific installation options for Windows and macOS, and also supports Linux installations through Flatpak or Snap. Its documentation explains how the software works, its security properties, usage, and contribution guidelines, indicating that it is intended for both end users and contributors.

NextcloudPi is a community project that packages Nextcloud into a ready-to-use appliance-style distribution. It targets users who want a preconfigured Nextcloud deployment on Raspberry Pi, Odroid, Rock64, virtual machines, LXD/LXC containers, or a Debian-based host without assembling the stack manually. The project bundles the application with supporting services and administration tools, including a web panel and a command-line configuration utility. It also provides a wide set of convenience and hardening extras such as HTTPS redirection, backups and restores, firewalling, fail2ban, dynamic DNS, automatic updates, and storage features like BTRFS snapshots and USB automounting.

Filestash is presented as a storage-agnostic file management platform aimed at users who need to work across many storage backends and protocols. It started as a Dropbox-like file manager and expanded into a broader, plugin-based system where storage handlers, authentication logic, workflows, and even file viewers can be swapped or extended through plugins. The project is positioned for people and organizations that want a customizable layer on top of existing file infrastructure, such as FTP, SFTP, S3, SMB, WebDAV, and other protocols. It exposes universal access through a web client, APIs, and gateways, and it emphasizes extensibility for custom integrations, RBAC-based authorization, automated file workflows, and specialized file apps.