Find the best open-source alternatives to popular software.

BestAlternative helps you find self-hosted, privacy-friendly, free, and local-first replacements for paid software, compare the tradeoffs, and plan a practical migration path.

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Mattermost logo

Mattermost

Mattermost provides a flexible, open-source platform for secure team collaboration, designed for organizations with strict security and privacy requirements.

38,667
Other

Alternative to: Microsoft Teams

drawDB logo

drawDB

Free online database diagram editor with SQL generation. Create ER diagrams, visualize relationships, export scripts, and reverse engineer schemas - no signup required.

38,237
AGPL-3.0

Alternative to: Microsoft Visio

Umami logo

Umami

A lightweight, open-source alternative to Google Analytics that respects user privacy and provides valuable insights.

38,055
MIT

Alternative to: Google Analytics

ToolJet logo

ToolJet

Open-source low-code platform for creating custom internal tools, dashboards, and admin panels with a drag-and-drop interface

37,849
AGPL-3.0

Alternative to: Retool

Harness logo

Harness

Streamline code delivery with an open-source CI/CD platform featuring Git integration, fast pipelines, and hosted development environments.

37,651
Apache-2.0

Alternative to: GitHub

ERPNext logo

ERPNext

Open-source ERP solution offering modules for accounting, inventory, HR, CRM, and more. Customizable and scalable for businesses of all sizes.

37,597
GPL-3.0

Alternative to: SAP

Directus logo

Directus

A versatile headless CMS and API engine that simplifies data management, content creation, and application development.

37,163
Other

Alternative to: WordPress

CopilotKit logo

CopilotKit

Integrate production-ready AI copilots into any product quickly and easily with CopilotKit's open-source platform.

36,456
MIT

Alternative to: LangChain

LibreChat logo

LibreChat

Free, open source AI chat platform compatible with any AI provider. Offers a wide range of features, including agents, code interpreter, and multimodal capabilities.

36,397
MIT

Alternative to: Grok

Nextcloud logo

Nextcloud

Nextcloud offers on-premises file sync, sharing and collaboration platform with advanced security and privacy features.

36,333
AGPL-3.0

Alternative to: Microsoft Teams

Open-Notebook logo

Open-Notebook

Open-source note-taking and research platform combining AI capabilities with complete privacy control. Features podcast generation, content integration, and customizable workflows.

36,333
MIT

Alternative to: NotebookLM

Khoj logo

Khoj

An open-source personal AI application that helps you find answers, understand documents, and create new content with ease.

36,201
AGPL-3.0

Alternative to: Claude

HashiCorp Vault logo

HashiCorp Vault

HashiCorp Vault is a powerful tool for managing secrets, protecting sensitive data, and controlling access using identity-based security.

36,060
Other

Alternative to: 1Password

Keycloak logo

Keycloak

Comprehensive open source identity management solution offering single sign-on, social login, and fine-grained authorization for applications and services.

35,995
Apache-2.0

Alternative to: Auth0

Medusa logo

Medusa

Flexible, customizable e-commerce platform with headless architecture, built-in features, and extensive plugin ecosystem for scalable online stores.

35,581
MIT

Alternative to: Shopify

Chatwoot logo

Chatwoot

An open-source customer engagement platform that unifies multiple channels, enabling businesses to provide seamless support and build lasting relationships.

35,473
Other

Alternative to: Manychat

Refine logo

Refine

A React-based framework for rapid development of internal tools, admin panels, and dashboards with powerful data handling capabilities.

35,457
MIT

Alternative to: Retool

Continue logo

Continue

Open-source AI code assistant that connects models and context to build custom autocomplete and chat experiences inside your IDE.

35,315
Apache-2.0

Alternative to: Claude Code

1Panel logo

1Panel

Comprehensive web-based tool for Linux server administration with integrated website, database, container, and LLM management capabilities.

35,240
GPL-3.0

Alternative to: Plesk

Tailscale logo

Tailscale

Deploy a modern WireGuard-based VPN with zero configuration. Connect devices securely across clouds, VPCs, and on-premises networks without firewall rules.

34,801
BSD-3-Clause

Alternative to: Zerotier

Postiz logo

Postiz

Postiz offers an all-in-one solution for scheduling posts, creating content, and analyzing performance across multiple social networks.

34,266
AGPL-3.0

Alternative to: HootSuite

Kitty logo

Kitty

High-performance terminal emulator with GPU acceleration, graphics support, and advanced scripting capabilities for developers and system administrators.

34,242
GPL-3.0

Alternative to: Warp

PostHog logo

PostHog

All-in-one product analytics platform. Track user behavior, run experiments, and make data-driven decisions to grow your product.

34,231
Other

Alternative to: Google Analytics

Qdrant logo

Qdrant

Qdrant is an open-source vector database that provides high-performance similarity search for AI and machine learning applications.

33,779
Apache-2.0

Alternative to: Supabase

Pythagora logo

Pythagora

A VS Code extension that uses AI to help developers plan, write, test, and deploy full-stack web applications with minimal coding required.

33,776
Other

Alternative to: Lovable

CasaOS logo

CasaOS

CasaOS is an open-source personal cloud system that makes it easy to set up and manage your own home server

33,748
Apache-2.0

Alternative to: Umbrel

Dokploy logo

Dokploy

Streamline your deployment process with Dokploy. Manage applications and databases on any VPS using Docker and Traefik for improved performance and security.

33,655
Other

Alternative to: Vercel

Tabby logo

Tabby

Self-hosted AI coding assistant that enhances productivity with context-aware suggestions and privacy-focused implementation.

33,483
Other

Alternative to: Claude Code

Lightpanda logo

Lightpanda

Purpose-built headless browser that delivers 10x faster performance and 10x lower memory usage compared to Chrome headless for web automation and AI workflows.

33,439
AGPL-3.0

Alternative to: Browserbase

Ntfy logo

Ntfy

A lightweight, open-source solution for sending real-time notifications to your devices, with end-to-end encryption and no sign-up required.

32,999
Apache-2.0

Alternative to: LogSnag