Alternatives and similar repositories for recaptcha

Users that are interested in recaptcha are comparing it to the libraries listed below

• facebookarchive / php-graph-sdk
  The Facebook SDK for PHP provides a native interface to the Graph API and Facebook Login. https://developers.facebook.com/docs/php
  ☆3,199Updated 3 years ago
• aws / aws-sdk-php
  Official repository of the AWS SDK for PHP (@awsforphp)
  ☆6,144Updated this week
• sendgrid / sendgrid-php
  The Official Twilio SendGrid PHP API Library
  ☆1,519Updated 5 months ago
• mailgun / mailgun-php
  Mailgun's Official SDK for PHP
  ☆1,126Updated 4 months ago
• maxmind / GeoIP2-php
  PHP API for GeoIP2 webservice client and database reader
  ☆2,436Updated this week
• thephpleague / oauth2-client
  Easy integration with OAuth 2.0 service providers.
  ☆3,746Updated 3 weeks ago
• googleapis / google-api-php-client
  A PHP client library for accessing Google APIs
  ☆9,627Updated 3 months ago
• stripe / stripe-php
  PHP library for the Stripe API.
  ☆3,912Updated this week
• serbanghita / Mobile-Detect
  Mobile_Detect is a lightweight PHP class for detecting mobile devices (including tablets). It uses the User-Agent string combined with sp…
  ☆10,654Updated 3 months ago
• ezyang / htmlpurifier
  Standards compliant HTML filter written in PHP
  ☆3,219Updated 3 weeks ago
• paypal / PayPal-PHP-SDK
  PHP SDK for PayPal RESTful APIs
  ☆37Updated last year
• cocur / slugify
  Converts a string to a slug. Includes integrations for Symfony, Silex, Laravel, Zend Framework 2, Twig, Nette and Latte.
  ☆2,902Updated 11 months ago
• thephpleague / oauth2-server
  A spec compliant, secure by default PHP OAuth 2.0 Server
  ☆6,613Updated 3 months ago
• swiftmailer / swiftmailer
  Comprehensive mailing tools for PHP
  ☆9,510Updated 3 years ago
• ircmaxell / password_compat
  Compatibility with the password_* functions that ship with PHP 5.5
  ☆2,142Updated last year
• defuse / php-encryption
  Simple Encryption in PHP.
  ☆3,844Updated last year
• Seldaek / monolog
  Sends your logs to files, sockets, inboxes, databases and various web services
  ☆21,302Updated 2 weeks ago
• twigphp / Twig
  Twig, the flexible, fast, and secure template language for PHP
  ☆8,315Updated 2 weeks ago
• phpDocumentor / phpDocumentor
  Documentation Generator for PHP
  ☆4,251Updated last week
• php-webdriver / php-webdriver
  PHP client for Selenium/WebDriver protocol. Previously facebook/php-webdriver
  ☆5,202Updated this week
• googleapis / google-api-php-client-services
  ☆1,263Updated last week
• phpseclib / phpseclib
  PHP Secure Communications Library
  ☆5,507Updated last month
• mpdf / mpdf
  PHP library generating PDF files from UTF-8 encoded HTML
  ☆4,560Updated last month
• thephpleague / csv
  CSV data manipulation made easy in PHP
  ☆3,428Updated last month
• matthiasmullie / minify
  CSS & JavaScript minifier, in PHP. Removes whitespace, strips comments, combines files (incl. @import statements and small assets in CSS …
  ☆2,022Updated last month
• mrclay / minify
  Combines. minifies, and serves CSS or Javascript files
  ☆3,004Updated 6 months ago
• KnpLabs / snappy
  PHP library allowing thumbnail, snapshot or PDF generation from a url or a html page. Wrapper for wkhtmltopdf/wkhtmltoimage
  ☆4,452Updated 2 months ago
• filp / whoops
  PHP errors for cool kids
  ☆13,252Updated last week
• guzzle / guzzle
  Guzzle, an extensible PHP HTTP client
  ☆23,402Updated 4 months ago
• briannesbitt / Carbon
  A simple PHP API extension for DateTime.
  ☆16,635Updated this week