HubSpot's Pro or enterprise CMS is an excellent tool for the savvy, conversion-focused marketing and sales leaders. Whilst this is a premium CMS with a monthly subscription fee, its inbuilt features really negate the cost once you add up the features like 3rd party add-ons to a free CMS.
Bludit - Bludit is a web application to build your own website or blog in seconds, it's completely free and open source. Markdown support.
WordPress - WordPress is web software you can use to create a beautiful website or blog. We like to say that WordPress is both free and priceless at the same time.
Grav - The modern open source flat-file CMS
Craft CMS - Content management system built on Yii PHP Framework
WonderCMS - WonderCMS is the smallest flat file CMS. Completely free, open source, privacy oriented for over 12 years.
Drupal - Drupal - the leading open-source CMS for ambitious digital experiences that reach your audience across multiple channels. Because we all have different needs, Drupal allows you to create a unique space in a world of cookie-cutter solutions.