Open-source alternatives to popular software
OSS Alternatives covers a small number of proprietary tools in depth rather than a large, shallow directory. Each page below ranks genuinely open-source alternatives by GitHub activity and spells out license, self-hosting, and pricing so you can pick one with confidence.
Browse by category
Communication alternatives
Wati
WhatsApp business messaging and automation
1 alternative
HelpDesk
Ticketing system for customer support
6 alternatives
Threema
Privacy-focused secure messenger
1 alternative
MailerLite
Email marketing for small businesses
8 alternatives
Knock
Notification infrastructure for product teams
1 alternative
tawk.to
Free live chat and customer messaging
5 alternatives
Canary Mail
AI-powered email client
4 alternatives
AutoSend
Email sending platform for developers
10 alternatives
ActiveCampaign
Email marketing and automation platform
8 alternatives
Gather
Virtual office and spaces for remote teams
1 alternative
NotificationAPI
Notification infrastructure for email, SMS, push, and in-app messages
2 alternatives
Mailgun
Transactional email API for developers
8 alternatives
Google Meet
Video conferencing from Google
3 alternatives
Guilded
Chat platform for gaming communities
8 alternatives
Klaviyo
Email and SMS marketing automation for ecommerce
6 alternatives
Coursera
Online learning platform with university courses and certificates
3 alternatives
Intercom
Customer messaging and support platform with chat, help desk, and AI agents
9 alternatives
Superhuman Mail
Fast, keyboard-driven email client with AI features
4 alternatives
Twilio
Communications APIs for SMS, voice, video, and email
3 alternatives
Freshdesk
Customer support helpdesk and ticketing platform
7 alternatives
Customer.io
Messaging automation platform for email, push, SMS, and in-app messages
4 alternatives
Zendesk
Customer service and support ticketing platform
9 alternatives
Open
Customer support and messaging platform
4 alternatives
Mailchimp
Email marketing and automation platform for newsletters and campaigns
11 alternatives
Zoom
Video conferencing and online meetings platform
3 alternatives
Slack
Team communication
18 alternatives
Microsoft Teams
Team chat, meetings, calls, and collaboration
21 alternatives
Discord
Community chat, voice, and video
11 alternatives
Apple Mail
Built-in email app for macOS, iOS, and iPadOS
3 alternatives
Udemy
Online course marketplace for learning and selling courses
3 alternatives
Brevo
Email marketing, SMS, CRM, and marketing automation platform
10 alternatives
Skype
Video calling and messaging app retired by Microsoft in 2025
5 alternatives
Skool
Community, courses, and events platform for creators and coaches
7 alternatives
LiveChat
Live chat and customer support software for websites
6 alternatives
Telegram
Cloud-based messenger with chats, channels, groups, bots, and calls
5 alternatives
Private messaging, group chats, calls, and media sharing
2 alternatives