What to Post
The part of social media that has nothing to do with software: deciding what goes in the post. These pieces cover what a small business can talk about when nothing new has happened this week, how often to post before it stops paying for itself, and whether the things everyone still does out of habit, hashtags among them, do anything at all. Where a piece quotes a number it says where the number came from, because most posting advice is somebody's preference dressed up as a rule.
All 25 guides
How the Instagram algorithm works in 2026, according to Meta's own system cards
Every guide to this quotes an Instagram blog post dated May 2023. Meta also publishes nine Instagram ranking system cards, six of them updated in 2026, naming the exact predictions its models make. One of them says the quality of your post is scored by an LLM.
Best time to post on Instagram, and why the studies are twelve hours apart
Later says 5am. Sprout Social says 2pm. Hootsuite says 5pm. RecurPost says 9pm. Four of the largest datasets in the industry, covering billions of engagements between them, and they do not agree about what time of day it is.
LinkedIn headline examples: we measured 62 of the ones everyone hands out
Every example headline in the two top ranking guides is longer than 60 characters, and 82 percent are longer than 70, which is roughly where a headline stops being visible in the places it is actually seen. None of them gets past 110 characters, out of the 220 available. They are all crammed into the one zone that is too long to read and too short to index.
The best time to post on Facebook: four studies, seven hours apart, and the metric Facebook switched off
Hootsuite says Tuesday at 5am. Sprout Social says Tuesday between midday and 8pm. Same platform, same year, same question, and a seven hour gap between the answers. The four studies agree on exactly one thing, and the reason they cannot do better is that Facebook stopped publishing the data that would settle it.
YouTube banner size, and the 82 percent of it nobody is guaranteed to see
Upload 2560 x 1440 under 6MB. Then design inside a strip in the middle that is 60 percent of the width and 29 percent of the height, because that is the only part YouTube promises to show on every device. The rest is decoration for televisions.
YouTube thumbnail size, and the number every guide is still copying
1280 x 720 has been the answer for a decade and it is now the wrong one. YouTube asks for 3840 x 2160 and takes a 50MB file from a desktop. The old number survives because YouTube itself still serves a file at exactly that size, which is a better reason than most guides have.
Instagram highlight covers: the size, the arithmetic nobody shows, and the set that actually earns its place
Every guide gives a different safe area for a highlight cover: 600 pixels, 700, 720. All three are guesses at one number you can work out exactly, and it is 764. Here is the geometry, and then the harder question, which is what the five circles under your bio should say.
Instagram captions: the length everyone recommends is the one the data likes least
Almost every caption guide tells you two things: keep it under 125 characters so it fits above the fold, and finish with a block of hashtags. One of those lands in the worst performing bracket anybody has measured. The other has been impossible since Instagram capped hashtags at five.
The best time to post on TikTok: four studies, eleven million posts, and one window they all agree on
Buffer says Saturday is the best day. Sprout Social says do not post on Saturday. Metricool says Saturday is the quietest day of the week. Four large studies contradict each other on every single day, one slot survives all four, and TikTok's own description of the For You feed never mentions posting time at all.
The best time to post on YouTube: two studies, one overlap, and the thumbnail that matters more
Buffer measured 1.8 million videos and SocialPilot measured 301 thousand, and they disagree about Wednesday. Where they agree is worth having: Sunday morning for long-form, Friday evening for Shorts. And both agree the clock moves results less than the thumbnail does.
Caption ideas that are actually captions: twenty finished posts, each with the caption it should get
Lists of caption ideas are three hundred one-liners with no picture attached, which is like a list of punchlines with no setup. Here are twenty finished posts and, under each one, the caption we would publish with it, written out, with the reasoning shown.
Instagram bio ideas: twenty bios written out in full, not described
Every list of Instagram bio ideas tells you to be authentic and add a call to action. This one writes the actual bio, twenty times, for twenty different kinds of business, inside the 150 characters you actually get, with the feed each bio has to live above.
