Google will turn off reCAPTCHA v1 on March 31, 2018. Starting in November 2017, a small percentage of reCAPTCHA v1 traffic will begin to show a notice informing users that the old API will soon be retired. Any calls to the v1 API will not work after March 31, 2018.

Fully customize version 1 of the widget, especially when a fully responsive solution is needed for your site. The visitors need to copy the words seen or heard.

Layout
Default layout Default
The default layout
Bootstrap layout Bootstrap
A layout that is Bootstrap-based
Icons layout Icons
A layout with icons as links (uses Bootstrap for tooltips)
Your layout One or more layout(s) that you have created as template override(s), with names different than default or Bootstrap
CSS classes Classes you want to affect to the outer most layer of the widget
CSS styles Styles you want to use to improve the look of the widget. Styles will be minimized

Note The audio challenges use Flash. This technology is phasing out of the browsers, therefore your visitors may just see a link to download an mp3 file and never automatically hear the audio file.

How to make the widget responsive

This will mostly depend on the CSS you will use to style the widget.
In order to make the image responsive, you will most likely need to add the following CSS:

#recaptcha_image {
    width: auto !important;
    height: auto!important;
}
#recaptcha_challenge_image {
    max-width: 100%;
}

Internationalization

The reCaptcha widget will be fully translated IF the Custom reCaptcha plugin supports the language requested (all the Google supported languages for the widget version 1 are available in the plugin).

Troubleshoot

Problem The Bootstrap template's input field is not responsive

Solution You can fix this with CSS, for instance (change the code to fit your template)

@media screen and (max-width: 767px) {
    .g-recaptcha .input-append { width: 60px; }
}

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