Here are some of our favorites. All of the tools on this page are either open source, free to use, or have a free pricing tier. Please suggest additional resources if you know of any that aren't listed here. Some other good places to look are The New Dynamic and the list of Awesome Static Website Services. Also make sure to check out the list of static site hosts for services designed to host your static sites.
Building a community is an important part of many sites, and these tools help with that by providing commenting, discussion forums, and other community functionality.
Discussion and comments.
Lets people comment on content on your site using their Facebook account.
A hosted comment system that works for every website.
IntenseDebate is a feature-rich comment system.
Inline discussion widget similar to Medium.
A hosted comment system to help engage readers with your content.
A GitHub issue based commenting system.
Turn your static site into a revenue generating machine with these tools that add commercial capabilities.
Add an online store for free in 5 minutes.
With FoxyCart, developers create flexible, powerful custom ecommerce in less time.
Themes, images, and other content to use for your static site. Also includes tools and services to work with content.
Image back-end for web and mobile developers.
Spiffy HTML5 site templates.
Free (do whatever you want) high-resolution photos.
These tools help edit your static site, and some even provide full CMS capabilities either locally or hosted.
CMS and blogging engine built for developers.
Build static websites, have your team and clients update inline.
Contentful is a content management developer platform with an API at its core.
DatoCMS is a fully customizable administrative area for your static websites.
A headless CMS that manages your content, not your workflow.
An open source CMS for static site generators.
A CMS backend for your websites & apps.
Prose is a content editor for GitHub designed for managing websites.
The fully customizable, headless CMS.
A simple, powerful, hosted CMS.
Collecting data can often be just as important as publishing it. These services support forms submission, processing, and analytics in a variety of ways.
Free and open source forms via email that keeps your email address private.
Simple form processing and response retrieval via email.
Probably the simplest HTML form builder.
Just point your form at FormKeep.
Forms via email.
Collect and organize information big & small with Google Forms.
Send a form from your static site to our url and we'll deliver it to your inbox.
Turn form submissions into emails.
Simple Form allows you to setup forms with any kind of data (including file uploads).
Staticman handles user-generated content for you and transforms it into data files that sit in your GitHub repository.
These tools let you add structured or unstructured search to your static site.
Hosted Search API that delivers instant and relevant results from the first keystroke.
Cloud search service for web and mobile app development.
Google Custom Search
Add a search box to your homepage to help people find what they need on your website.
Simple full-text search in your browser.
Sharing is caring.
Make your content shareable with just one click.
Simple Sharing Buttons Generator
Create light-weight, mobile-friendly sharing buttons for Facebook, Twitter, Google+ and other social networks.