ALTCHA AlternativesAnti-Spam Tools and other similar apps like ALTCHA

ALTCHA is described as 'Uses a proof-of-work mechanism to protect your website, APIs, and online services from spam and unwanted content. Unlike other CAPTCHA solutions, ALTCHA is free, open-source and self-hosted, does not use cookies nor fingerprinting, does not track users, and is fully' and is a Anti-Spam tool in the online services category. There are more than 10 alternatives to ALTCHA for a variety of platforms, including Web-based, SaaS, Self-Hosted, JavaScript and PHP apps. The best ALTCHA alternative is reCAPTCHA, which is free. Other great apps like ALTCHA are hCaptcha, mosparo, mCaptcha and Friendly Captcha.

filter to find the best alternatives

ALTCHA alternatives are mainly Anti-Spam Tools but may also be Bot Protection Services. Filter by these or use the filter bar below if you want a narrower list of alternatives or looking for a specific functionality of ALTCHA.
ALTCHA iconALTCHA
  4
  • ...

ALTCHA uses a proof-of-work mechanism to protect your website, APIs, and online services from spam and unwanted content. Unlike other CAPTCHA solutions, ALTCHA is free, open-source and self-hosted, does not use cookies nor...

More about ALTCHA
More about ALTCHA
ALTCHA alternatives page was last updated Mar 6, 2025
  Suggest Alternatives
  1. reCAPTCHA icon
    reCAPTCHA icon

    reCAPTCHA

     127 likes
    Copy a direct link to this comment to your clipboard

    reCAPTCHA is a free service that protects your site from spam and abuse, using risk analysis techniques to tell humans and bots apart.

    24 reCAPTCHA alternatives
    reCAPTCHA screenshot 1

    License model

    • Freemium • Proprietary

    Application type

    Platforms

    • Online

    reCAPTCHA Features

    1.  Spam Filter
    2.  Captcha Recognition
    An example of an additional challenge
    reCAPTCHA iconALTCHA Icon

    reCAPTCHA VS ALTCHA

    Is reCAPTCHA a good alternative to ALTCHA?
     

    • reCAPTCHA is the most popular Web-based alternative to ALTCHA.

    • reCAPTCHA is the most popular free alternative to ALTCHA.

    • reCAPTCHA is Freemium and ProprietaryALTCHA is Free and Open Source
  2. hCaptcha icon
    hCaptcha icon

    hCaptcha

     12 likes
    Copy a direct link to this comment to your clipboard

    hCaptcha is designed to solve the most labor intensive problem in machine learning: labeling massive amounts of data in a timely, affordable, and reliable way.

    25 hCaptcha alternatives
    hCaptcha screenshot 1

    License model

    • Freemium • Proprietary

    Application type

    Platforms

    • Online
    hCaptcha screenshot 1
    hCaptcha screenshot 2

    Properties

    1.  Privacy focused

    Features

    1.  Captcha
    2.  Bot detection
    3.  Web-Based
    4.  GDPR Compliant
    hCaptcha iconALTCHA Icon

    hCaptcha VS ALTCHA

    Is hCaptcha a good alternative to ALTCHA?
     
  4. mosparo icon
    mosparo icon

    mosparo

     4 likes
    Copy a direct link to this comment to your clipboard

    mosparo is the modern solution for protecting your online forms from spam. The protection method is quite simple: mosparo blocks spam using rules matching the form’s data. The detection method is comparable to an e-mail spam filter.

    20 mosparo alternatives
    A screenshot from the software mosparo with the empty project list.

    License model

    • Free • Open Source

    Application type

    Platforms

    • Online
    • Self-Hosted
    • Python
    • JavaScript
    • Drupal
    • Django
    • PHP
    • Mautic
    • Wordpress
    A screenshot from the page where the user can create a new project. It contains a form with the most important fields for a new project.
    A screenshot of the dashboard of the software mosparo. It shows the chart with the submissions and a counter for rules and rulesets.
    +9
    A screenshot from the list of rule types, from which the user has to choose one before he can continue.

    Properties

    1.  Privacy focused

    Features

    1.  Spam Filter
    2.  Self-hosted
    3. WordPress icon  WordPress Integration
    4. Drupal icon  Drupal Integration
    mosparo iconALTCHA Icon

    mosparo VS ALTCHA

    Is mosparo a good alternative to ALTCHA?
     

    • mosparo is the most popular Self-Hosted alternative to ALTCHA.

    • mosparo is the most popular Open Source alternative to ALTCHA.

    • mosparo is Free and Open SourceALTCHA is also Free and Open Source
    • mosparo is Privacy focusedALTCHA is not according to our users
  5. mCaptcha icon
    mCaptcha icon

    mCaptcha

     3 likes
    Copy a direct link to this comment to your clipboard

    A no-nonsense CAPTCHA system with seamless UX | Backend component.

    25 mCaptcha alternatives
    mCaptcha screenshot 1

    License model

    • Free • Open Source

    Application type

    Platforms

    • Online
    • Self-Hosted
    • Software as a Service (SaaS)

    Properties

    1.  Privacy focused

    Features

    1.  Ad-free
    2.  Captcha
    3.  Rust
    mCaptcha iconALTCHA Icon

    mCaptcha VS ALTCHA

    Is mCaptcha a good alternative to ALTCHA?
     

    • mCaptcha is the most popular SaaS alternative to ALTCHA.

    • mCaptcha is Free and Open SourceALTCHA is also Free and Open Source
    • mCaptcha is Privacy focusedALTCHA is not according to our users
  6. Friendly Captcha icon
    Friendly Captcha icon

    Friendly Captcha

     10 likes
    Copy a direct link to this comment to your clipboard

    Friendly Captcha is a tool for preventing spam on your website.

    19 Friendly Captcha alternatives
    Friendly Captcha screenshot 1

    License model

    • Freemium • Proprietary

    Application types

    Platforms

    • Online
    • Software as a Service (SaaS)

    Properties

    1.  Privacy focused

    Features

    1.  GDPR Compliant
    2.  Bot detection
    3.  Mobile friendly
    4.  Captcha
    5. WordPress icon  WordPress Integration
    6.  No Tracking
    7.  European data privacy
    8.  Web-Based
    9.  Ad-free
    10.  Spam Filter
    11.  Dark Mode
    Friendly Captcha iconALTCHA Icon

    Friendly Captcha VS ALTCHA

    Is Friendly Captcha a good alternative to ALTCHA?
     
  7. Cloudflare Turnstile icon
    Cloudflare Turnstile icon

    Cloudflare Turnstile

     2 likes
    Copy a direct link to this comment to your clipboard

    Turnstile is Cloudflare's smart CAPTCHA alternative. It automatically chooses from a rotating suite of non-intrusive browser challenges based on telemetry and client behavior exhibited during a session.

    11 Cloudflare Turnstile alternatives

    License model

    • Free • Proprietary

    Platforms

    • Online
    • JavaScript
    • Software as a Service (SaaS)

    Cloudflare Turnstile Features

    1.  Web-Based
    2.  Fraud detection
    3.  Bot detection
    Cloudflare Turnstile iconALTCHA Icon

    Cloudflare Turnstile VS ALTCHA

    Is Cloudflare Turnstile a good alternative to ALTCHA?
     
  9. Procaptcha icon
    Procaptcha icon

    Procaptcha

     8 likes
    Copy a direct link to this comment to your clipboard

    Prosopo Procaptcha redefines user verification with a unique approach that emphasizes privacy, security, and decentralization. It's a pioneering solution designed to offer an alternative to conventional, centralized CAPTCHA systems that often compromise user privacy.

    18 Procaptcha alternatives
    Procaptcha screenshot 1

    License model

    • Freemium • Open Source

    Application types

    Platforms

    • Online
    • Software as a Service (SaaS)
    Prosopo home page
    Procaptcha screenshot 2

    Properties

    1.  Privacy focused

    Features

    1.  Bot detection
    2.  Captcha
    3.  Spam Filter
    4.  Ad-free
    5.  Integrated Spam Protection
    Procaptcha iconALTCHA Icon

    Procaptcha VS ALTCHA

    Is Procaptcha a good alternative to ALTCHA?
     
  10. Trustcaptcha icon
    Trustcaptcha icon

    Trustcaptcha

     2 likes
    Copy a direct link to this comment to your clipboard

    Trustcaptcha is your user-friendly CAPTCHA solution for preventing spam and bot attacks on your website with a focus on GDPR compliance and UX.

    9 Trustcaptcha alternatives
    Contact form sample
    Demo field

    License model

    • Freemium • Proprietary

    Application types

    Platforms

    • Online
    • Spring
    • Kotlin
    • Rust
    • Ruby
    • Python
    • .NET Framework
    • Craft CMS
    • React
    • Groovy
    • JavaScript
    • Angular
    • Software as a Service (SaaS)
    • Scala
    • PHP
    • Go (Programming Language)
    • Typescript
    • Java
    • Wordpress
    • Node.JS
    • Vue.js

    Properties

    1.  Privacy focused

    Features

    1.  Ad-free
    2.  Captcha
    3.  Web-Based
    4.  Mobile friendly
    5.  European data privacy
    6.  GDPR Compliant
    7.  Bot detection
    8. WordPress icon  WordPress Integration
    Trustcaptcha iconALTCHA Icon

    Trustcaptcha VS ALTCHA

    Is Trustcaptcha a good alternative to ALTCHA?
     
  11. MTcaptcha icon
    MTcaptcha icon

    MTcaptcha

     3 likes
    Copy a direct link to this comment to your clipboard

    MTCaptcha is a smart captcha service that prioritizes privacy and accessibility. It offers an adaptive invisible noCaptcha that is easy for humans but hard for bots, making verification frictionless. MTCaptcha is GDPR and WCAG compliant, ensuring that your data is never sold or...

    18 MTcaptcha alternatives
    MTCAptcha Standard

    License model

    • Freemium • Proprietary

    Platforms

    • Software as a Service (SaaS)

    MTcaptcha Features

    1.  GDPR Compliant
    2.  Captcha
    MTCaptcha comparision
    MTCAptcha Mini
    +2
    MTCaptcha Dark Theme
    MTcaptcha iconALTCHA Icon

    MTcaptcha VS ALTCHA

    Is MTcaptcha a good alternative to ALTCHA?
     

  12. EU Captcha

     Like this app
    Copy a direct link to this comment to your clipboard

    Multilingual captcha developed by and for EU countries.

    19 EU Captcha alternatives

    License model

    • Free • Open Source

    Platforms

    • Self-Hosted

    EU Captcha Features

    1.  Spam Filter
    2.  European data privacy
    3.  Captcha
    ALTCHA Icon

    EU Captcha VS ALTCHA

    Is EU Captcha a good alternative to ALTCHA?
     
  13. CaptchaText icon
    CaptchaText icon

    CaptchaText

     Like this app
    Copy a direct link to this comment to your clipboard

    A zero database architecture, powered by a proprietary hybrid in-memory indexing engine algorithm, that enables CAPTCHA authentication to be performed using minimal data bits against server memory.

    11 CaptchaText alternatives
    CaptchaText screenshot 1

    License model

    • Freemium • Proprietary

    Platforms

    • Online
    • Software as a Service (SaaS)

    CaptchaText Features

    1.  Captcha Recognition
    2.  Captcha
    CaptchaText screenshot 1
    CaptchaText screenshot 2
    CaptchaText iconALTCHA Icon

    CaptchaText VS ALTCHA

    Is CaptchaText a good alternative to ALTCHA?
     
  14. IconCaptcha icon
    IconCaptcha icon

    IconCaptcha

     Like this app
    Copy a direct link to this comment to your clipboard

    conCaptcha is a self-hosted captcha which is faster, more user-friendly and more customizable than other captchas - available for PHP and ASP.NET websites. Users no longer have to read any annoying text images, solve difficult math equations or play any puzzle games.

    16 IconCaptcha alternatives
    IconCaptcha screenshot 1

    License model

    • Free • Open Source

    Platforms

    • Self-Hosted

    IconCaptcha Features

    1.  Bots
    2.  Captcha
    IconCaptcha iconALTCHA Icon

    IconCaptcha VS ALTCHA

    Is IconCaptcha a good alternative to ALTCHA?
     
12 of 12 ALTCHA alternatives