XML- offers a free online sitemap generator, as well as an unlimited and a pro version. The free generator is super simple and only requires 4 quick steps. Set the frequency to how often the content on your selected URL will change, include the date it was last modified, and use the automatically calculated priority option to indicate the URL’s importance relative to other pages on the site. XML- also offers some additional SEO tools including an XML sitemap validator, competitor analysis, keyword density calculator, and a SERP page checker. I haven’t used any of these tools personally, but they appear to be worth a look if you’re using this tool already.