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@@ -2668,6 +2668,7 @@ See also [Infrastructure](#infrastructure)
 * [EcoIndex](http://www.ecoindex.fr/) - :fr: [FR] L’objectif d’EcoIndex est d’aider le plus grand nombre à prendre conscience de l’impact environnemental de l’internet et de proposer des solutions concrètes pour réduire cet impact. EcoIndex vous propose donc une analyse automatique de premier niveau pour vous aider à identifier rapidement et gratuitement des sites web / services en ligne à ausculter en priorité.
 * [WAVE Web Accessibility Evaluation Tool](https://wave.webaim.org/) - WAVE can identify many accessibility and Web Content Accessibility Guideline (WCAG) errors, but also facilitates human evaluation of web content. **Bonus** [WAVE Browser Extensions](https://wave.webaim.org/extension/)
 * [Contrast Ratio](https://contrast-ratio.com) - Easily calculate color contrast ratios. Passing WCAG was never this easy!
+* [Nibbler](https://nibbler.silktide.com/) - is a free tool for testing websites. Enter the address of any website and Nibbler will give you a report scoring the website out of 10 for key areas, including accessibility, SEO, social media and technology.
 
 > Bookmarklets
 * [mourner/bullshit.js](https://github.com/mourner/bullshit.js) - A bookmarklet for translating marketing speak into human-readable text. 💩 **See also** : [Home Page](https://mourner.github.io/bullshit.js/)
@@ -6779,6 +6780,7 @@ rpm --rebuilddb
 * [WAVE Web Accessibility Evaluation Tool](https://wave.webaim.org/) - WAVE can identify many accessibility and Web Content Accessibility Guideline (WCAG) errors, but also facilitates human evaluation of web content. **Bonus** [WAVE Browser Extensions](https://wave.webaim.org/extension/)
 * [Contrast Ratio](https://contrast-ratio.com) - Easily calculate color contrast ratios. Passing WCAG was never this easy!
 * [debugCSS](https://imbrianj.github.io/debugCSS/) - (X)HTML debugging tool built with CSS | debugCSS is meant to be loaded on an existing page to highlight potentially broken, malformed or legacy (X)HTML. Not all "errors" are created equally, so they are color coded to highlight severity. Green is "probably not a big problem", yellow is "worth looking at" and red is "you really should fix this." **See also** [GitHub repository](https://github.com/imbrianj/debugCSS)
+* [Nibbler](https://nibbler.silktide.com/) - is a free tool for testing websites. Enter the address of any website and Nibbler will give you a report scoring the website out of 10 for key areas, including accessibility, SEO, social media and technology.
 
 ## Design Humor
 * [Jon Moore](https://medium.com/ux-power-tools/100-excuses-for-designers-517344cdd910) - 100 Excuses for Designers, Because sometimes you need one!
@@ -6916,6 +6918,7 @@ Run Lighthouse on an emulated mobile device on a 3G network. Running the test wi
 * [Revenge.css](http://heydonworks.com/revenge_css_bookmarklet/) - is a CSS bookmarklet that reports bad html using pseudo content. If the page you use it with has malformed links, deprecated attributes, <div>s inside inline elements, inaccessible buttons, badly nested sections or other errors, you'll see some ugly, pink errors written in nobody's favourite font: Comic Sans. **See also** [GitHub repository](https://github.com/Heydon/REVENGE.CSS)
 * [debugCSS](https://imbrianj.github.io/debugCSS/) - (X)HTML debugging tool built with CSS | debugCSS is meant to be loaded on an existing page to highlight potentially broken, malformed or legacy (X)HTML. Not all "errors" are created equally, so they are color coded to highlight severity. Green is "probably not a big problem", yellow is "worth looking at" and red is "you really should fix this." **See also** [GitHub repository](https://github.com/imbrianj/debugCSS)
 * [Contrast Ratio](https://contrast-ratio.com) - Easily calculate color contrast ratios. Passing WCAG was never this easy!
+* [Nibbler](https://nibbler.silktide.com/) - is a free tool for testing websites. Enter the address of any website and Nibbler will give you a report scoring the website out of 10 for key areas, including accessibility, SEO, social media and technology.
 
 # Windows
 * [NSSM](https://nssm.cc/commands) - the Non-Sucking Service Manager