Open Source WhatsApp API Compared: 5 Options (2026)
Searching for an open source WhatsApp API turns up a handful of projects that look alike and differ in ways that only show up after you deploy them. This page puts five of them side by side using what each project's own repository says today: license, how it talks to WhatsApp, and what you have to run.
One thing is the same for all of them. They connect a regular WhatsApp account, not Meta's official Business API, so there is no Meta Business verification and no per-message fee, and WhatsApp's usage policies apply to the number you link. WuzAPI's own README warns about it explicitly, and the rest are in the same position.
The five, side by side
| Project | Built with | License | What you run |
|---|---|---|---|
| WAHA | TypeScript, four engines: WEBJS (browser), NOWEB, GOWS, WPP | Apache 2.0 | One Docker image with Swagger and a dashboard |
| Evolution API | TypeScript, Baileys, plus the official Cloud API | Apache 2.0 with extra conditions | Docker, PostgreSQL or MySQL, Redis recommended |
| WuzAPI | Go, whatsmeow | MIT | One service, SQLite by default or PostgreSQL |
| WPPConnect Server | TypeScript, WPPConnect | Apache 2.0 | Docker with Chromium and a manager interface |
| WSAPI community edition | The same API as WSAPI Cloud | Free to self-host | Docker Compose with Redis |
Facts as of November 2, 2026.
What the table does not say
WAHA is the one with the most choices inside one image. Since version 2026.6 its former Plus features are part of the core image, and it is updated often, with a release on October 28. The price of that flexibility is picking an engine: the browser-based ones (WEBJS and WPP) behave differently from the websocket ones.
Evolution API is the broadest. Besides WhatsApp over Baileys it supports the official Cloud API, and it ships integrations for Typebot, Chatwoot, OpenAI, Dify and queues such as RabbitMQ, Kafka and SQS. Read the license before you commit: it is Apache 2.0 plus two conditions, one about keeping its logo and copyright in its console and one requiring a visible notice when it is part of your project. Its latest tagged release is 2.3.7 from December 2025, with commits as recent as July 2026.
WuzAPI is the smallest to operate. It is a Go service on the whatsmeow library, it keeps state in SQLite until you need PostgreSQL, and it signs webhooks with HMAC, with retries you can configure.
WPPConnect Server wraps the WPPConnect library in a REST service. It needs Chromium, so the container includes a browser, and it comes with a manager interface for sessions.
WSAPI is also open source, and that is the difference worth knowing: the community edition is the same API as WSAPI Cloud. You can self-host it with Docker Compose, with Redis Streams for events and multiple accounts per deployment, and move to managed hosting later without rewriting your integration. The open source page lists what stays Cloud only, such as the admin portal and support.
How to choose
- You want one project that runs several engines and has a dashboard: WAHA.
- You want chatbots and CRM tools already wired in, or the official Cloud API next to the unofficial one: Evolution API.
- You want the lightest service to operate: WuzAPI.
- Your team already uses WPPConnect: its server.
- You want to start self-hosted and keep the option of someone else running it: WSAPI. A managed instance costs $5 a month, flat, with no per-message fees and with buttons and lists included.
If the real question is who runs the server rather than which project, our comparison of self-hosted and cloud and the one with WAHA go deeper.
Try the WSAPI side
Sending a message is one request. With placeholder credentials it answers with a 401 that names the problem, which is how you know the endpoint is reachable:
curl -X POST https://api.wsapi.chat/messages/text \
-H "x-api-key: your-api-key" \
-H "x-instance-id: your-instance-id" \
-H "Content-Type: application/json" \
-d '{"to": "1234567890", "text": "Hello!"}'Replace the placeholders with your own and the same request sends a message. The quickstart covers creating the instance and linking a number, and the free trial lasts 14 days with no credit card.
FAQ
Which open source WhatsApp API is the easiest to run?
WuzAPI has the fewest moving parts: one Go service and SQLite by default. WAHA is the easiest to try, with a single Docker image and a dashboard.
Are these projects really free?
Yes to the license, and every one asks you to provide and maintain the server.
Can WhatsApp restrict my number?
WSAPI connects a regular WhatsApp account, so WhatsApp's usage policies apply and accounts that send unsolicited bulk messages can be limited. The same holds for every project in this comparison.