PHP - antispam code with numbers and letters (CAPTCHA)

October 2016

On many sites, the forms are accompanied by an insert request to copy a randomly generated code.

Such a system called CAPTCHA, used to limit abusive automated mailings (SPAM).

The following sites offer free tools in PHP, to put such a system on its website:
  • CryptoPHP, Free, PHP> = 4.3.0. Available in plugins for WordPress, wpMu, Symfony and Guppy.
  • ReCaptcha, Free, operates Web Service (online)
  • WebSpamProtect, Fee, PHP, Perl, ASP or ASP.NET
  • WP Captcha Free Free shows no code to copy, it is based on a system of self-generated hash making it impossible to add automated comments
  • ProtectWebFormis an online service offering a captcha, coupled to an audio system (for blind persons)

Related :

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