Social media image and video sizes for 2026
Pixel sizes, aspect ratios, file size caps and video lengths per platform, taken from the same rules Join Postly uses to check posts before they're scheduled.
Updated 7 min read
Read the guideBlog
Social media and SEO guides from the Join Postly blog
The Join Postly blog publishes practical, fact-checked guides on social media scheduling, platform limits, SEO and AI search. It's written for small businesses, creators, marketers and agencies who run their own channels and websites. Every guide shows when it was last updated, and we only state limits we can source.
All guides
Social media Social media How to schedule Instagram posts, Reels and Stories
From switching to a professional account to scheduling Reels, Stories and a first comment, plus the file rules and daily limits that make posts fail.
Updated 6 min read
Read the guideSocial media How to find your best time to post on social media
Why generic posting-time charts mislead, and a step-by-step test you can run on your own accounts to find the hours that work for your audience.
Updated 6 min read
Read the guideSocial media What is a link in bio page, and what should go on it?
A link in bio page turns the single link on your profile into a short menu. Here's what to include, how to order it and how to see which links get used.
Updated 6 min read
Read the guideSEO Semantic SEO: entities, attributes and topical maps
How search engines think about things rather than strings, and how to turn that into a topical map with pillars, hubs, articles and a clear internal linking plan.
Updated 6 min read
Read the guideSEO How to run a free SEO site audit, step by step
The checks that matter in a technical SEO audit, in the order worth doing them, with what each problem looks like and how to fix it.
Updated 7 min read
Read the guideAI search What is llms.txt, and does your website need one?
A plain explanation of the llms.txt proposal: where it came from, what the file looks like, what it can't do, and an honest view on whether to publish one.
Updated 6 min read
Read the guideSEO Keyword clustering by SERP overlap, explained
Group keywords by the results they share, not by how similar they look. The method, the threshold, the pillar rule and how to turn clusters into pages.
Updated 6 min read
Read the guide
About the Join Postly blog
How often is the Join Postly blog updated?
New guides are added when they're ready rather than on a fixed schedule. Every guide shows its published date and its last-updated date at the top, and we revise a guide when a platform changes the rules it describes.
Who writes the guides on the Join Postly blog?
The Join Postly team, the same people who build the scheduler and the Postly Rank SEO add-on. Each guide is credited to the team rather than to an invented author.
Where do the numbers in Join Postly blog guides come from?
Platform limits such as file sizes, video lengths and caption lengths come from the rules Join Postly uses to check posts before they're scheduled, the same data behind the Post limits page. We don't quote surveys or averages we can't verify, and we flag figures that platforms change often.
Do the blog guides only work if I use Join Postly?
No. The methods work with any tool, including the platforms' own apps. Where Join Postly has a feature that helps, the guide says exactly what it does, and what it doesn't do.
Can I suggest a topic for the Join Postly blog?
Yes. Email info@joinpostly.com with the question you'd like answered. Topics that many people ask about are written first.