ALTCHA is a free, open-source alternative to CAPTCHA that uses a proof-of-work system to protect websites from spam and unwanted content while respecting user privacy. It can be configured globally or on specific forms.
ALTCHA provides a free, open-source Captcha alternative utilizing a proof-of-work mechanism to safeguard your website against spam and unwanted content. ALTCHA ensures robust spam protection without compromising user privacy.
Integrations supported
- Self-hosted
- Sentinel
- SaaS API (deprecated)
Post-Installation
- Configure ALTCHA globally on the CAPTCHA configuration form via: /admin/config/people/captcha
- Configure ALTCHA on specific forms via: /admin/config/people/captcha/captcha-points
- Users with the
administer altchapermission can configure ALTCHA via: /admin/config/people/captcha/altcha
Requirements
This module depends on the CAPTCHA module.
Additional features
ALTCHA Obfuscate
This feature provides support for the obfuscation mode of the ALTCHA widget, and helps protect sensitive information from bots.
The submodule adds obfuscation field formatters for e-mail, telephone and text fields.
Versioning
There are currently 2 supported branches:
- 1.x: ALTCHA v2 widget. View specific configuration docs here.
- 2.x: ALTCHA v3 widget with improved algorithm and additional display options. View specific configuration docs here.
Alternative modules
Friendly Captcha - Alternative proof-of-work CAPTCHA solution.
CAPTCHA - See the list of other CAPTCHA modules.
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Depends on
Dependencies of the latest stable release
Required by
Tracked projects that depend on this one
No tracked projects depend on this one yet.
Activity
Release Timeline
Releases
| Version | Type | Core | PHP | Release date | |
|---|---|---|---|---|---|
| 2.0.0-rc1 | Pre-release | 10–11 | Oct 14, 2026 | ||
| 1.2.1 | Stable | 10–11 | Oct 14, 2026 | ||
| 2.0.0-beta1 | Pre-release | 10–11 | Jul 17, 2026 | ||
| 1.2.0 | Stable | 10–11 | Jul 17, 2026 | ||
| 2.0.x-dev | Dev | 10–11 | Jul 16, 2026 | ||
| 1.1.0 | Stable | 10–11 | Feb 18, 2026 | ||
| 1.1.0-rc1 | Pre-release | 10–11 | Nov 7, 2025 | ||
| 1.0.0 | Stable | 10–11 | Dec 6, 2024 | ||
| 1.0.0-beta1 | Pre-release | 10–11 | Nov 28, 2024 | ||
| 1.0.x-dev | Dev | 10–11 | Oct 23, 2024 |