Bootstrap

Bootstrap is a open-source collection of tools for creating browser sites and applications.

Free Open Source Self-Hosted JavaScript HTML5 Boilerplate

Foundation

Foundation is an easy to use, powerful, and flexible framework for building rapid prototypes and production code on any kind of device.

Free Open Source Web

Semantic UI

Semantic empowers designers and developers by creating a shared vocabulary for UI.

Free Open Source Web

UIKit

A lightweight and modular front-end framework for developing fast and powerful web interfaces. ui framework full HTML / CSS, javascript component , form, theme , dropdown , responsive ... More full than bootstrap or foundation

Free Open Source Web

Skeleton

Skeleton is a small collection of CSS & JS files that can help you rapidly develop sites that look beautiful at any size, be it a 17" laptop screen or an iPhone.

Free Open Source Web

Purecss

A set of small, responsive CSS modules that you can use in every web project.

Free Open Source Web

MUI

MUI is a lightweight HTML/CSS/JS framework that follows Google's Material Design guidelines.

Free Open Source Web

Gridlex

Simple. Robust. Responsive. Flexible. Based on Flexbox (CSS Flexible Box Layout Module), Gridlex is a very simple css grid system to quickly create modern layouts and...

Free Open Source Web Self-Hosted

Spectre.css

Lightweight, responsive and modern CSS framework for faster and extensible development.

Free Open Source Web Self-Hosted

Picnic CSS

Unpack your meal and get coding. An invasive CSS library to get your style started.

Free Open Source Self-Hosted CSS

Flexbox Grid

A grid system based on the flex display property.

Free Open Source Web Self-Hosted

Juiced (a Flexbox CSS Framework)

Juiced has many of the same layout features that you know and love, but improves upon them with better mobile targeting, custom column ordering, better alignment...

Free Open Source Web Self-Hosted

960 Grid System

The 960 Grid System is an effort to streamline web development workflow by providing commonly used dimensions, based on a width of 960 pixels. There are two variants: 12...

Free Open Source Mac OS X Windows Linux BSD Web

Element UI

Element, a Vue 2.0 based component library for developers, designers and product managers.

Free Open Source Web Self-Hosted JavaScript Vue.js CSS

react-md

This project's goal is to be able to create a fully accessible material design styled website using React Components and Sass.

Free Open Source Self-Hosted

Susy

Susy: un-obtrusive grid system for designers, built on Compass and Sass

Free Open Source Web

Microsoft Web Framework

MWF is a system that allows site authors to consider how best to tell the story of Microsoft products and services with confidence that the modular pieces will support...

Free Open Source Self-Hosted

Frow (flex row) CSS Grid System

Frow is an HTML and CSS framework for creating quick, responsive, mobile-first projects on the web.

Free Open Source Web Self-Hosted

Responsive Grid System

This is the Responsive Grid System, a quick, easy and flexible way to create a responsive web site.

Free Open Source Web