Katalon costs $25/mo.
These cost $0.
2 free alternatives to Katalon, checked for license, recent activity and real adoption. Each one tells you the catch, so you can switch with your eyes open.
The top-rated free, open-source replacement for Katalon is Keploy (Open Source Open Source). Across this category, 1 self-hostable tool is available (including Keploy). Switching a 5-person team saves up to $1,500/year compared to Katalon's $25/mo subscription.
The catch: Requires self-hosting setup, updates, and server maintenance compared to managed Katalon.
Katalon vs Free Alternatives
Quick side-by-side comparison · $0/mo vs $25/mo
| Alternative | Type | License | Where It Runs | Stars | Head-to-Head |
|---|---|---|---|---|---|
| Keploy | open source | Open Source | Self-host | ★ 19.5k | Katalon vs Keploy → |
| Hercules | open source | Open Source | Local | ★ 1.2k | Katalon vs Hercules → |
The picks
2 open source · ranked by fit
- 01
Keploy
open sourceOpen SourceSelf-host19.5knov 2026Captures real API traffic and dependency calls via eBPF to generate tests and mocks automatically, then replays them in CI to catch regressions before they ship.
The catch vs KatalonRequires self-hosting setup, updates, and server maintenance compared to managed Katalon.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/keploy/keploy or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 02
Hercules
open sourceOpen SourceLocal1.2knov 2026Hercules is the first open-source testing agent, enabling zero-code, zero-maintenance UI, API, security, accessibility, and visual validations.
The catch vs KatalonCommunity-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
- platforms
- desktopcross-platformone-click install
- install
- Clone https://github.com/test-zeus-ai/testzeus-hercules or deploy with Docker Compose
- setup
- Download the native package or installer for your operating system.
- your data
- All application data lives locally on your own machine.
- checked
- 2026-11-07
Katalon Head-to-Head Comparisons (2027)
Side-by-side trade-off breakdowns · 2 free alternatives
Frequently Asked Questions
Direct answers · Katalon open-source replacements
What is the best free alternative to Katalon?+
The top free alternative to Katalon is Keploy (open source, Open Source). Captures real API traffic and dependency calls via eBPF to generate tests and mocks automatically, then replays them in CI to catch regressions before they ship. Other popular Katalon replacements include Hercules.
Can I self-host a free replacement for Katalon?+
Yes. Of the 2 free alternatives to Katalon, 1 can be self-hosted on your own server or local machine: Keploy (Open Source).
How much does switching from Katalon to a free alternative save?+
Katalon starts at $25/month per seat ($300/year). Switching a 5-person team to a free alternative like Keploy saves $1,500 per year in software subscription fees.
Should I vibe-code or build my own Katalon clone from scratch?+
Our build verdict for Katalon is NO (use a free alternative, save the tokens). Instead of paying recurring SaaS fees for Katalon or rebuilding it from scratch, deploy one of the 2 battle-tested open-source alternatives like Keploy.
What is the catch when switching from Katalon to Keploy?+
Requires self-hosting setup, updates, and server maintenance compared to managed Katalon.
