Best Open-Source Software Alternatives, by Category
Open-source tools let you read the code, avoid lock-in and often run the software yourself. These are the open-source options we list as alternatives to popular paid software. We list 224 of them across 24 categories; each category shows the most-recommended first.
Open-source notes & docs tools
- JoplinAn open-source note app with a web clipper, Markdown notes and end-to-end encrypted sync.Alternative to Evernote, OneNote, Obsidian
- BookStackA free, self-hosted wiki organised as shelves, books and pages.Alternative to Confluence, SharePoint
- LogseqAn open-source outliner for networked notes, journals and tasks, stored locally.Alternative to Notion, Obsidian
- SimplenotePlain, fast, free notes synced across devices.Alternative to Evernote, Google Keep
- AppFlowyAn open-source, Notion-style workspace with pages, databases and kanban boards that you can self-host.Alternative to Notion
- OutlineA fast team wiki with a Markdown editor that you can also self-host.Alternative to Confluence
Open-source project management tools
- GristA relational spreadsheet with Python formulas, available open source.Alternative to Airtable, Microsoft Excel, Google Sheets
- BaserowAn open-source no-code database with a familiar spreadsheet interface.Alternative to Airtable
- ExcalidrawA free, open-source whiteboard with a hand-drawn look.Alternative to Miro
- GanttProjectFree desktop Gantt chart software.Alternative to Microsoft Project
- NocoDBAn open-source Airtable alternative that turns any database into a smart spreadsheet.Alternative to Airtable
- OpenProjectOpen-source project management with Gantt charts, boards and time tracking.Alternative to Asana
- PlaneAn open-source project and issue tracker you can self-host.Alternative to Jira
- PlankaAn open-source, self-hosted Trello-style kanban board.Alternative to Trello
- ProjectLibreFree, open-source desktop project management with Gantt charts.Alternative to Microsoft Project
- TaigaOpen-source agile project management with kanban and scrum boards.Alternative to Trello
Open-source design tools
- draw.ioFree, open-source diagramming in the browser or desktop.Alternative to Lucidchart, Microsoft Visio
- FreeCADFree, open-source parametric 3D CAD.Alternative to AutoCAD
- GIMPThe best-known free, open-source image editor for Windows, Mac and Linux.Alternative to Adobe Photoshop
- InkscapeFree, open-source vector graphics editor.Alternative to Adobe Illustrator
- KritaFree, open-source software focused on digital painting and illustration.Alternative to Adobe Photoshop
- LibreCADFree, open-source 2D CAD.Alternative to AutoCAD
- PenpotOpen-source design and prototyping built on open web standards; self-hostable.Alternative to Figma
Open-source email & social media tools
- DubOpen-source link management and attribution.Alternative to Bitly
- KuttFree, open-source URL shortener.Alternative to Bitly
- ListmonkA free, open-source, self-hosted newsletter and mailing-list manager.Alternative to Mailchimp
- PostizAn open-source social media scheduler you can self-host.Alternative to Buffer
Open-source sales & CRM tools
Open-source analytics tools
- PostHogProduct analytics, session replay, feature flags and experiments in one open-source platform.Alternative to Google Analytics, Hotjar, Mixpanel
- MatomoFull-featured open-source analytics with 100% data ownership.Alternative to Google Analytics, PostHog, Amplitude
- PlausibleLightweight, privacy-friendly, open-source web analytics on one simple page.Alternative to Google Analytics, Mixpanel, PostHog
- OpenReplayOpen-source session replay you can self-host.Alternative to Hotjar
- UmamiOpen-source, privacy-focused analytics you can self-host for free.Alternative to Google Analytics
Open-source developer & hosting tools
- CoolifyAn open-source, self-hosted Heroku and Vercel alternative for your own server.Alternative to Heroku, Vercel, Portainer
- .NET MAUIMicrosoft’s cross-platform native UI framework for .NET.Alternative to Flutter, React Native
- AppwriteAn open-source backend platform for web and mobile apps.Alternative to Firebase, Supabase
- CapacitorRun web apps natively on iOS and Android.Alternative to Flutter, React Native
- ClineAn open-source coding agent for VS Code that works with many models.Alternative to Cursor, Claude Code
- IonicBuild mobile apps with web technologies.Alternative to Flutter, React Native
- Kotlin MultiplatformShare Kotlin code across Android, iOS, web and desktop.Alternative to Flutter, React Native
- NhostPostgres, GraphQL, auth and storage as a service.Alternative to Firebase, Supabase
- PocketBaseAn open-source backend in a single file: database, auth and file storage.Alternative to Firebase, Supabase
- SupabaseAn open-source Firebase alternative built on Postgres, with auth, storage and realtime.Alternative to Firebase, Replit
- ZedA fast, open-source code editor with built-in AI features.Alternative to Cursor, Visual Studio Code
- AngularGoogle’s full-featured TypeScript framework.Alternative to React
- AppsmithOpen-source low-code builder for internal tools.Alternative to Retool
- BootstrapThe classic CSS framework with ready-made components.Alternative to Tailwind CSS
- BrunoOffline-first, open-source API client that stores collections in git.Alternative to Postman
- BudibaseOpen-source low-code platform for internal apps and workflows.Alternative to Retool
- BulmaModern CSS framework based on Flexbox.Alternative to Tailwind CSS
- Chakra UIAccessible React component library.Alternative to Tailwind CSS
Open-source automation tools
- ActivepiecesAn open-source, no-code automation tool.Alternative to Zapier, n8n
- Home AssistantOpen-source smart-home automation that runs locally.Alternative to IFTTT
- Node-REDOpen-source flow-based programming for automations and IoT.Alternative to n8n
- WindmillOpen-source platform for scripts, workflows and internal apps.Alternative to n8n
Open-source AI tools
- AiderOpen-source AI pair programming in your terminal, working with your git repo.Alternative to Claude Code
- ContinueOpen-source AI code assistant for VS Code and JetBrains.Alternative to GitHub Copilot
- CrewAIFramework for orchestrating teams of collaborating AI agents.Alternative to LangChain
- DSPyStanford’s framework for programming — not prompting — language models.Alternative to LangChain
- Gemini CLIGoogle’s open-source AI agent for the terminal.Alternative to Claude Code
- HaystackOpen-source framework for production RAG and LLM pipelines.Alternative to LangChain
- LanguageToolA multilingual grammar and style checker with an open-source core.Alternative to Grammarly
- LiteLLMOpen-source gateway that calls 100+ model APIs in one format.Alternative to OpenRouter
- LlamaIndexFramework for connecting LLMs to your data and building agents.Alternative to LangChain
- MastraTypeScript framework for AI agents, workflows and RAG.Alternative to LangChain
- Semantic KernelMicrosoft’s open-source SDK for building AI agents in C#, Python and Java.Alternative to LangChain
- SillyTavernOpen-source interface for roleplay with the AI model of your choice.Alternative to Character.AI
- Vercel AI SDKTypeScript toolkit for building AI apps and agents.Alternative to LangChain
Open-source support & forms tools
Open-source communication & scheduling tools
- ElementSecure, decentralised messaging on the Matrix protocol.Alternative to Slack, Discord, WhatsApp
- MattermostOpen-source, self-hosted team messaging for secure environments.Alternative to Slack, Discord, Microsoft Teams
- Rocket.ChatOpen-source team chat with full data control.Alternative to Slack, Discord, Microsoft Teams
- ZulipOpen-source chat organised by topic-based threads.Alternative to Slack, Discord, Microsoft Teams
- Cal.comOpen-source scheduling infrastructure with a generous free plan.Alternative to Calendly, Doodle
- Jitsi MeetFree, open-source video meetings with no account required.Alternative to Zoom, Skype
- CapAn open-source Loom alternative for recording and sharing screen videos.Alternative to Loom
- RalllyOpen-source group meeting polls — a simple Doodle alternative.Alternative to Doodle
- ThunderbirdFree, open-source desktop email client from Mozilla.Alternative to Outlook
- TutaEncrypted email and calendar from Germany (formerly Tutanota).Alternative to Gmail
Open-source files & documents tools
- NextcloudOpen-source file sync and collaboration you host yourself.Alternative to Dropbox, Google Drive, OneDrive
- DocumensoAn open-source DocuSign alternative you can self-host.Alternative to DocuSign, Adobe Acrobat Sign
- Stirling-PDFOpen-source PDF tools you can self-host so files never leave your server.Alternative to Adobe Acrobat
Open-source websites & commerce tools
- WordPressThe open-source CMS with countless themes and plugins.Alternative to Webflow, Wix, Squarespace
- GhostOpen-source publishing with built-in newsletters and paid memberships.Alternative to WordPress, Kit (ConvertKit), Substack
- AstroAn open-source framework for fast, content-focused sites.Alternative to WordPress, Next.js
- MedusaAn open-source commerce platform for developers.Alternative to Shopify, WooCommerce
- PolarAn open-source billing platform for developers selling software.Alternative to Gumroad, WHOOP
- JoomlaFree, open-source CMS.Alternative to Drupal
- PayloadAn open-source, code-first headless CMS for Next.js.Alternative to WordPress
- PrestaShopOpen-source e-commerce popular in Europe.Alternative to WooCommerce
- StrapiOpen-source headless CMS.Alternative to Drupal
- WebstudioAn open-source visual website builder.Alternative to Webflow
- WooCommerceFree, open-source e-commerce for WordPress.Alternative to Shopify
Open-source security tools
- BitwardenAn open-source password manager with a generous free plan.Alternative to LastPass, NordPass
- KeePassXCA free, open-source, offline password manager.Alternative to LastPass, NordPass
- KeycloakOpen-source identity and access management.Alternative to Auth0, Okta
- Mullvad VPNPrivacy-first VPN you can use without an email address.Alternative to NordVPN, Surfshark
- Private Internet AccessConfigurable VPN with open-source apps.Alternative to NordVPN, Surfshark
- Proton VPNSwiss, open-source VPN with a genuinely free plan.Alternative to NordVPN, Surfshark
- InfisicalOpen-source secrets management platform.Alternative to HashiCorp Vault
- IVPNTransparent, privacy-focused VPN.Alternative to NordVPN
- OpenBaoOpen-source secrets management fork of Vault.Alternative to HashiCorp Vault
- SemgrepFast static analysis with custom rules.Alternative to Snyk
- Supabase AuthOpen-source auth built into Supabase.Alternative to Auth0
Open-source office & productivity tools
- LibreOfficeFree, open-source office suite: Writer, Calc, Impress and more.Alternative to Microsoft Word, Microsoft Excel, PowerPoint
- ONLYOFFICEOpen-source office suite highly compatible with Microsoft formats.Alternative to Microsoft Word, Google Docs, Google Workspace
- wallabagOpen-source, self-hostable read-it-later app.Alternative to Pocket
Open-source social & messaging tools
- SignalEnd-to-end encrypted messaging and calls from a non-profit foundation.Alternative to WhatsApp, Telegram, Snapchat
- MastodonOpen-source, ad-free microblogging across thousands of independent servers.Alternative to X (Twitter), Reddit
- BlueskyA decentralised social network with custom feeds and an open protocol.Alternative to X (Twitter)
- LemmyOpen-source, federated link aggregator — a decentralised take on Reddit.Alternative to Reddit
- MumbleFree, open-source, low-latency voice chat you can host yourself.Alternative to Discord
- PixelfedAd-free, federated photo sharing — an open-source Instagram alternative.Alternative to Instagram
Open-source music, video & creative tools
- BlenderFree, open-source 3D suite for modelling, animation, VFX and rendering.Alternative to After Effects
- BookWyrmOpen-source, federated social reading and reviewing.Alternative to Goodreads
- darktableFree, open-source RAW photo workflow.Alternative to Lightroom
- JellyfinFree, open-source media server with no premium tier.Alternative to Plex
- KodiFree, open-source media centre for local media.Alternative to Plex
- LMMSFree, open-source music production software.Alternative to FL Studio
- PeerTubeOpen-source, federated video hosting.Alternative to YouTube
- RawTherapeeFree, open-source RAW image processing.Alternative to Lightroom
Open-source finance & payments tools
Open-source HR & operations tools
Open-source data & BI tools
- MetabaseOpen-source BI anyone on the team can use.Alternative to Grafana, Tableau, Power BI
- Apache SupersetOpen-source data exploration and dashboards.Alternative to Tableau, Power BI, Looker
- LightdashOpen-source BI built on your dbt project.Alternative to Looker, Metabase
- MeltanoOpen-source, code-first ELT built on Singer.Alternative to Fivetran, Airbyte
- AirbyteOpen-source data integration with hundreds of connectors.Alternative to Fivetran
- ClickHouseFast open-source columnar database for analytics.Alternative to Databricks
- dltOpen-source Python library for loading data.Alternative to Airbyte
- EvidenceOpen-source BI as code with SQL and markdown.Alternative to Metabase
- GrafanaOpen-source dashboards for metrics, logs and traces.Alternative to Metabase
- SQLMeshOpen-source data transformation framework.Alternative to dbt
- ZabbixOpen-source infrastructure monitoring.Alternative to Grafana
Open-source infrastructure & DevOps tools
- RustDeskOpen-source remote desktop you can self-host.Alternative to TeamViewer, AnyDesk
- SigNozOpen-source, OpenTelemetry-native observability.Alternative to Datadog, Grafana
- XCP-ngOpen-source Xen-based virtualisation platform.Alternative to Proxmox, VMware
- AnsibleAgentless automation and configuration management.Alternative to Terraform
- Apache PulsarDistributed messaging and streaming with multi-tenancy.Alternative to Apache Kafka
- Apache SolrMature open-source enterprise search platform.Alternative to Elasticsearch
- CephOpen-source distributed object, block and file storage.Alternative to MinIO
- CockpitWeb-based Linux server administration, with container support.Alternative to Portainer
- ColimaMinimal container runtimes on macOS and Linux.Alternative to Docker
- CrossplaneManage cloud infrastructure through Kubernetes.Alternative to Terraform
- DockgeSelf-hosted manager for Docker Compose stacks.Alternative to Portainer
- GarageLightweight, geo-distributed S3-compatible storage.Alternative to MinIO
- GarnetMicrosoft Research’s Redis-compatible cache store.Alternative to Redis
- HeadscaleOpen-source, self-hosted Tailscale control server.Alternative to Tailscale
- IncusOpen-source system containers and VMs (community fork of LXD).Alternative to Docker
- JenkinsOpen-source automation server with a huge plugin ecosystem.Alternative to GitHub Actions
- K3sLightweight certified Kubernetes for edge and small clusters.Alternative to Kubernetes
- KeyDBMultithreaded, Redis-compatible database.Alternative to Redis
Open-source education & learning tools
Open-source marketplaces & web tools
- BraveFast browser that blocks ads and trackers by default.Alternative to Google Chrome
- FirefoxMozilla’s open-source, privacy-focused browser.Alternative to Google Chrome
- OpenStreetMapThe free, community-built map of the world.Alternative to Google Maps
- Organic MapsFree, offline, privacy-friendly maps based on OpenStreetMap.Alternative to Google Maps
- Zen BrowserOpen-source, Firefox-based browser with vertical tabs.Alternative to Google Chrome
Open-source gadgets & devices
Plans and licences change, so check each tool’s site for current details.