wptobe

The easiest, fastest and most reliable membership plugin
The wptobe-signinup plugin provides functions for member registration, login and member management required on the website, 
It focus on ease of use and fast speed and stability. It offers a Captcha function to protect against spam by default and easily change the design of any theme by selecting a pre-made template without any programming.
Member Registration, Login, Reset Password, Profile, Change Password. 
우커머스 쇼핑몰 체크아웃 국내 주소(Daum 우편번호 서비스) 사용 기능.
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The capcha can be used for sign-in/sign-up screen to prevent spam users.
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Each field can be edited and the position can be easily changed by drag-and-drop. The setting screen and the short code output are the same, so it is very intuitive and easy.
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It provides on/off switch to show or hide each field.
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It is possible to log in by email without username.
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You can set the page to be redirected after sign-in/sign-up.
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No need to put the short code directly in a page, just select it from the selection box.
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You can create different styles and change them whenever you want. For example, create a themeA, themeB C style whenever the theme changes, simply change it in the selection box to change the design. We provides Default/Black/Avada/Enfold design by default.
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It allows users to receive via email if they forget their password. The administrator can modify the content of the email to be sent.
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Members can change their current password to a new password on the profile page.
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It provides an html/css file that outputs sign-in/sign-up/profile independently, so you can easily change and copy it.
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You can reset the plug-in to the initial state at any time.
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<h4>User Guide</h4>
You can find user guide, installation and more detailed information about Wptobe-signinup on wptobe.com. 
* <a href="http://www.wptobe.com/wptobe-signinup" rel="nofollow ugc">User Guide</a>

Wptobe-signinup

Wptobe Signinup is a very light plugin that lets you easily and safely build sign in/up with designed page.

rtCamp

Shalin Shah

Nikhil Joshua

Chirag Mathur

Sagar Tamang

Ultra minimal plugin to let your users login to WordPress applications using their Google accounts. No more remembering hefty passwords!
<h3>Initial Setup</h3>
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Create a project from <a href="https://console.developers.google.com/apis/dashboard" rel="nofollow ugc">Google Developers Console</a> if none exists.
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Go to Credentials tab, then create credential for OAuth client.
<ul>
<li>Application type will be Web Application</li>
<li>Add <code>YOUR_DOMAIN/wp-login.php</code> in Authorized redirect URIs</li>
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This will give you Client ID and Secret key.
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Input these values either in <code>WP Admin > Settings > WP Google Login</code>, or in <code>wp-config.php</code> using the following code snippet:
<code>define( 'WP_GOOGLE_LOGIN_CLIENT_ID', 'YOUR_GOOGLE_CLIENT_ID' ); 
define( 'WP_GOOGLE_LOGIN_SECRET', 'YOUR_SECRET_KEY' );</code>
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</ol>
<h3>Browser support</h3>
<a href="https://developers.google.com/identity/gsi/web/guides/supported-browsers" rel="nofollow ugc">These browsers are supported</a>. Note, for example, that One Tap Login is not supported in Safari.
<h3>How to enable automatic user registration</h3>
You can enable user registration either by 
– Enabling Settings > WP Google Login > Enable Google Login Registration
OR
<ul>
<li>Adding 
<code>define( 'WP_GOOGLE_LOGIN_USER_REGISTRATION', 'true' );</code> 
in wp-config.php file.</li>
</ul>
Note: If the checkbox is ON then, it will register valid Google users even when WordPress default setting, under
Settings > General Settings > Membership > Anyone can register checkbox
is OFF.
<h3>Restrict user registration to one or more domain(s)</h3>
By default, when you enable user registration via constant <code>WP_GOOGLE_LOGIN_USER_REGISTRATION</code> or enable Settings > WP Google Login > Enable Google Login Registration, it will create a user for any Google login (including gmail.com users). If you are planning to use this plugin on a private, internal site, then you may like to restrict user registration to users under a single Google Suite organization. This configuration variable does that.
Add your domain name, without any schema prefix and <code>www,</code> as the value of <code>WP_GOOGLE_LOGIN_WHITELIST_DOMAINS</code> constant or in the settings <code>Settings > WP Google Login > Whitelisted Domains</code>. You can whitelist multiple domains. Please separate domains with commas. See the below example to know how to do it via constants: 
 <code>define( 'WP_GOOGLE_LOGIN_WHITELIST_DOMAINS', 'example.com,sample.com' );</code>
Note: If a user already exists, they will be allowed to login with Google regardless of whether their domain is whitelisted or not. Whitelisting will only prevent users from registering with email addresses from non-whitelisted domains.
<h3>Hooks</h3>
For a list of all hooks please refer to <a href="https://github.com/rtCamp/login-with-google#hooks" rel="nofollow ugc">this documentation</a>.
<h4>wp-config.php parameters list</h4>
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<code>WP_GOOGLE_LOGIN_CLIENT_ID</code> (string): Google client ID of your application.
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<code>WP_GOOGLE_LOGIN_SECRET</code> (string): Secret key of your application
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<code>WP_GOOGLE_LOGIN_USER_REGISTRATION</code> (boolean) (optional): Set <code>true</code> If you want to enable new user registration. By default, user registration defers to <code>Settings > General Settings > Membership</code> if constant is not set.
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<code>WP_GOOGLE_LOGIN_WHITELIST_DOMAINS</code> (string) (optional): Domain names, if you want to restrict login with your custom domain. By default, it will allow all domains. You can whitelist multiple domains.
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<h3>BTW, We’re Hiring!</h3>
<a href="https://rtcamp.com/careers/" rel="nofollow ugc"></a>

Log in with Google

In terms of ready-to-go possibilities, this plugin is the best free plugin for both Logging in and Registering with Google.

Wptobe-signinup vs Log in with Google