Description

This is ALTCHA Plugin version 1.

ALTCHA Plugin version 2 is now available, offering improved protection and enhanced reliability. An upgrade is recommended for all users.

Learn more | Installation guide | Migration guide

What’s new in version 2:

Effective: blocks 99% of spam and abuse attempts
Invisible for users: frictionless protection, no puzzles or CAPTCHAs
Works everywhere: plugin-agnostic Request Interceptor integrates with any form plugin
Handles heavy traffic: stay online with Under Attack Mode
Stops abuse at scale: firewall and rate limiting included
Privacy-first: 100% GDPR-compliant and fully accessible
Unlimited: no external services, unlimited verifications

Learn more about ALTCHA at altcha.org.

ALTCHA fournit une alternative de CAPTCHA libre et gratuite, utilisant un mécanisme de protection éprouvé contre les requêtes indésirables et le spam automatisé. Notre solution anti-indésirables permet une protection robuste sans compromettre les données personnelles des internautes.

Contrairement à d’autres solutions, ALTCHA est libre, gratuit et auto-hébergé. ALTCHA opère indépendamment de tout service externe, sans aucun cookie ou traçage des internautes, ce qui permet une conformité complète avec le RGPD.

Free Mode

The free self-hosted mode is enabled by default after installation. No additional setup is required, except enabling the integrations you need in the plugin settings.

Données personnelles

Aucun cookie, pas de traçage

ALTCHA met la confidentialité au centre de ses priorités en évitant l’utilisation de cookies et de toute technique de traçage.

Aucun service externe

Si elle opère en mode auto-hébergé (réglage par défaut), cette extension reste entièrement contenue au sein de votre installation WordPress, éliminant tout dépendance à un service externe. Vous pouvez décider d’utiliser la version SAAS de l’API de notre filtre anti-spam. Pour plus d’informations, consultez https://altcha.org (en anglais).

Mode opératoire

Cette extension opère sur deux modes. Vous pouvez choisir le mode que vous souhaitez utiliser dans les réglages (voir la rubrique API) :

Self-hosted – free, fully self-contained without external services.
Custom or SaaS API – requires a server such as ALTCHA Sentinel.

API REST

Cette extension utilise l’API REST de WordPress. Si vous utiliser des extensions qui désactivent l’API REST, assurez-vous que le point de terminaison /altcha/v1/challenge est autorisé.

Intégrations prises en charge

CoBlocks
Contact Form 7
Formulaires Elementor Pro
Thème Enfold
Formidable Forms
Forminator
GravityForms
Formulaires HTML
WPDiscuz
WPForms
WP-Members
Connexion, inscription et réinitialisation de mots de passe sur WordPress
Commentaires WordPress
WooCommerce
HTML personnalisé (avec un code court [altcha])

Code source

Tout le code source de l’extension et du widget ALTCHA est disponible sur GotHub. Dans ce répertoire source, vous trouverez aussi des version non minifiées des ressources Javascript et CSS :

Extension (en anglais) : https://github.com/altcha-org/wordpress-plugin
Widget ALTCHA (en anglais) : https://github.com/altcha-org/altcha

Conditions d’utilisation et politique de confidentialité du SAAS

Politique de confidentialité (en anglais) : https://altcha.org/privacy-policy
Conditions d’utilisation (en anglais) : https://altcha.org/terms-of-service

Captures d’écrans

CAPTCHA intuitif sans puzzle
Configuration
Protection de la page de connexion
Protection avec WPForms
Interface flottante du CAPTCHA

Installation

Téléchargez, installez et activez ALTCHA Spam Protection.

Ou sinon, installez l’extension manuellement :

Téléchargez le fichier .zip depuis la liste des versions.
Téléversez le dossier altcha dans /wp-content/plugins/
Activez l’extension dans le menu « extensions » de WordPress.
Review the settings and enable your integrations

Avis

Hiroshi 24 novembre 2025

its a simple plugin easy to setup and work well with my websites… so far eliminated almost all spam +1

abaantravis 22 novembre 2025

I personally find this plugin very useful and working just fine, no problems. I don’t understand why people here complain. Great work, thanks! And please keep this plugin alive.

sarahsolus 17 novembre 2025

The version 1 Altcha WordPress plugin was a promising, if not perfect, captcha plugin. Unfortunately, the developers got everything wrong with version 2. First of all, it can only be installed via the website, which is suspicious. There are no upgrade notes, which is an absolute no-go for commercial sites. Incidentally, a captcha that installs itself into all forms without being asked is a very bad idea. For example, Altcha v2 also activates when using form-like elements such as filter widgets for lists. Or in globally integrated service forms, so that the Altcha screen pops up on every page. We also suspect that Altcha v2 prevents AI search engines from crawling – this has not yet been verified, but it coincides with the use of the plugin. For all these reasons, we have decided to stop using the plugin for the time being.

Alwyn Barry 17 novembre 2025

Altcha v1 was brilliant – did just what I wanted seamlessly. Sadly when I installed v2 the login blocked for some users (and it was impossible to see why). I think the increased comms to the central system were to blame, but I’m not sure. I can’t switch back to v1 without having the ‘nag’ to upgrade constantly visible on the plugin page, and putting the shortcode back into all the forms. A quick switch to Cloudfare Turnstile and all is working nicely. Sad, though, because Altcha looked great.

riccardomercurio 7 novembre 2025

It is simple it works!

agent862 7 novembre 2025

It’s free, works without any API or cloud services, no cookies, which all means GDPR and other privacy regulations are in check. 👍

Lire les 21 avis

Contributeurs/contributrices & développeurs/développeuses

« ALTCHA Spam Protection » est un logiciel libre. Les personnes suivantes ont contribué à cette extension.

Daniel

“ALTCHA Spam Protection” a été traduit dans 2 locales. Remerciez l’équipe de traduction pour ses contributions.

Traduisez « ALTCHA Spam Protection » dans votre langue.

Le développement vous intéresse ?

Parcourir le code, consulter le SVN dépôt, ou s’inscrire au journal de développement par RSS.

Journal des modifications

1.26.3

Fixed possible replay attacks via salt splicing.

1.26.2

Updated readme for the new version 2.

1.26.1

Fix Elementor Pro Forms widget rendering

1.26.0

Added Formidable Forms integration
Fixed PHP warning in the verify function
ALTCHA Widget 2.2.2

1.25.0

Added hooks for improved customization and integration flexibility. [#45]

1.24.0

Fix issue with duplicate widget rendering in Elementor popups and WPDiscuz replies

1.23.0

Prise en charge de CoBlocks

1.22.1

Correction de la validation Gravity Forms avec un serveur personnalisé

1.22.0

Fix Forminator multi-page forms
Fix Gravity Forms with Sentinel and fields classification

1.21.0

ALTCHA Widget 2.0.2
Widget scripts are now injected only on pages, which include the widget
Support for custom Challenge URL and ALTCHA Sentinel

1.20.0

Intégration avec le thème Enfold (formulaires de contact et d’inscription newsletter)

1.19.0

Fix submit issues with Contact Form 7 + Conditional fields

1.18.0

Fix language with Contact Form 7

1.17.0

Update widget to 1.2.0
Widget removes support for Expires header fixing potential auto-revalidation issues
Widget script provided as a UMD module allowing for JS minification

1.16.0

Fix reply to comments from the admin page [#36]

1.15.0

Translations with gettext and automatic language detection [#33]

1.14.1

Fix the « Settings » link [#32]

1.14.0

Automatic language detection [#31]
Change placement of the « Settings » link in the plugin list [#32]

1.13.1

Ignore WooCommerce form submissions in WordPress integration [#30]

1.13.0

WooCommerce integration [#26]
Improved validation message [#27]
Password lost error message [#28]

1.12.0

HTML Forms – skip verification if the shortcode is not in the form markup [#23]

1.11.1

Fix Forminator compatibility issue

1.11.0

Added support for WP-Members

1.10.0

Added support for WPDiscuz

1.9.3

Fix REST API Cache-Control header

1.9.2

Enable Custom HTML (shortcode) integration by default when activated

1.9.1

PHP 7 support (replace str_contains by strpos) [#19]

1.9.0

Widget updated to version 1.0.0
CF7 – fix widget placement
Fix page caching

1.8.0

Shortcode (custom integration) – fix mode (SpamFilter)

1.7.0

HTML Forms – add Shortcode option

1.6.1

Fix WordPress login integration

1.6.0

Fix Elementor Pro Forms widget rendering
Fix Contact Form 7 widget position and shortcode support

1.5.0

Fix REST base URL (+ REST prefix removed from settings) [#13]

1.4.0

Support for Elementor Pro Forms
Widget updated to 0.6.7

1.3.1

Fix site_url parsing issue [#11]

1.3.0

Added support for custom REST API prefixes

1.2.0

Forminator – fix widget rendering with file input
Widget updated to 0.6.4

1.1.0

Shortcode – support for language attribute

1.0.0

Widget updated to 0.6.3

0.3.0

Added nonce sanitization
Removed server-side spam filter (required for Plugin Directory)

0.2.1

Fixes requested by Plugin Directory review
Fixed various Spam Filter issues

0.2.0

Widget updated to 0.6.0
Added support for Floating UI

0.1.7

Fix Forminator multi-step forms

0.1.6

Widget updated to 0.5.1

0.1.5

Fixes requested by Plugin Directory review

0.1.4

GravityForms – added label and description options
Altcha widget updated to 0.4.3

0.1.3

Fixed « lost password » verification bug
Altcha widget updated to 0.4.1

0.1.2

Fixed widgets footer link and log warnings

0.1.1

Widget v0.4.0
Challenge expiration

0.1.0

First version

Works well

Thank you!

Ruined by the devs

v1 was great; v2 – I had to uninstall

Useful and simple

Great plugin