Free tools

Two small tools for people who post to social platforms. No sign-up, nothing is sent to a server: they run in your browser.

Caption and media limits checkerPaste a caption and add the files you plan to post, and see whether they fit the limits cometpost enforces for Threads, Instagram and YouTube.
UTM link builderAdd utm_source, utm_medium and utm_campaign to a link so your analytics can tell which post sent a visitor.

These tools do not collect or store what you enter. The site's page-view analytics (see the Privacy Policy) is the only measurement on these pages.