STATIC COMPARISON / TIER B
Locust vs Tsung
Answer Locust is an open source, self-hosted load testing tool from Locust authors, scripted in Python. Tsung is an open source, self-hosted protocol and API load tool from Tsung community, scripted in Erlang, XML. The practical split is the authoring language: Python for Locust, Erlang, XML for Tsung.
Curator verdict
Both cover HTTP, HTTPS. On recorded coverage Tsung is the wider of the two (5 protocols against 3), which matters only if your workload actually uses the extra ones. Team language and existing tooling usually settle Locust against Tsung. Run the same scenario on both before you standardize; the rows below only tell you what is true on paper.
Spec matrix
| Field | Locust | Tsung |
|---|---|---|
| Vendor | Locust authors | Tsung community |
| Category | Load Testing | Protocol/API Load |
| License | Open Source | Open Source |
| Deployment | Self-hosted | Self-hosted |
| Status | Active | Active |
| First released | 2011 | 2001 |
| Pricing | Free; MIT License. | Free; GPL-2.0 license. |
| Scripting | Python | Erlang, XML |
| Protocols | HTTP, HTTPS, WebSocket | HTTP, HTTPS, WebDAV, LDAP, XMPP |
| OS support | Windows, macOS, Linux | Linux, macOS |
How to choose
- Only Locust records support for WebSocket — one hard requirement there decides the pair on its own.
- Only Tsung records support for WebDAV, LDAP, XMPP — one hard requirement there decides the pair on its own.
- Match the authoring language to the team: Locust means Python, Tsung means Erlang, XML.
- Open the Test Rig to compare license, deployment, protocol and OS rows side by side.
Need more than two tools or a shareable matrix? Use the live Test Rig from the directory compare tray.
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