Carousel maker
Type one idea per slide and get designed carousel slides: PNGs for Instagram or a PDF LinkedIn shows as a document.
Free tools for social media posts
Free browser tools for LinkedIn, YouTube, Instagram and cross-posting: format text, test thumbnails, split images and check every network’s limits. No sign-up.
By Mellow · UpdatedEach tool works in your browser without an account. Whatever you give it, a draft or an image, stays in the page: nothing is uploaded to Mellow, and nothing is posted anywhere. When you want to publish, Mellow Hub sends one post to up to nine networks, on its own or through Claude, ChatGPT and other AI assistants.
For every network
Social media character counter
Count one post against every network’s limit at once, with X’s weighted count and Bluesky’s graphemes.
Social media post checker
Check caption, title and media count against Mellow Hub’s input rules for each destination.
LinkedIn text formatter
Bold, italic, underlined text and bullet lists for LinkedIn posts, with a preview of where the post folds.
YouTube
YouTube thumbnail maker
Make a thumbnail from your photo and a bold headline in four layouts, check it at Up next size and export 1280×720 or 4K.
YouTube thumbnail tester
See a thumbnail in YouTube’s home feed, search and sidebar at their real sizes, then export it at 1280×720 under 2 MB.
Instagram grid maker
Split one image into 3, 6, 9 or 12 posts that line up on your profile, numbered in the order to post them.
Instagram carousel splitter
Cut a wide image into seamless carousel slides at 4:5, 3:4 or 1:1, ready to swipe.
Also free to read
- Social media image sizes for every network on one page, each from the network’s own help.
- Answers about cross-posting and scheduling, one question per page, each with the network’s own rules and dated sources.
- The rules for every network that Hub checks before it sends a post.
- Instagram content calendar, a two- or four-week plan you can download as a CSV.
- All guides, from content calendars to connecting an AI assistant.