Social media agency / Instagram + TikTok
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Varmerk/Guides

How the platforms actually behave.

One question per page, answered in the first sentence, then the steps for iPhone, Android and desktop. Every claim names the help page it came from.

Sections 5Platforms Instagram, TikTok, FacebookPrice Free, no signup

Every guide.

The whole library in one place, most searched first. Pick a section to see just that one.

1 to 24 of 72 articles, most searched first

Posting to TikTokThe best time to post on TikTokThe best time to post on TikTok, by three studies of millions of posts that give three different answers. All three tables, and how to read your own data.Who sees whatDoes Instagram notify when you screenshot?Does Instagram notify when you screenshot? Only a disappearing photo or video in a DM, or anything in vanish mode. Stories, posts and reels: no.Posting and ReelsHow to post on Instagram, every formatHow to post a photo, a carousel, a Reel and a story on Instagram, from a phone or a computer, with the limits: 20 slides, 5 hashtags, 1080 pixels wide.Who sees whatHow to turn off vanish mode on InstagramHow to turn off vanish mode on Instagram: open the chat and swipe up. What happens to the messages, why it turned on by itself, and what to do if that fails.Times, sizes, limitsHow to use YouTube chaptersHow to use YouTube chapters: timestamps in the description, starting at 00:00, at least three in order, each over 10 seconds. The rules, and what breaks them.Posting and ReelsThe best time to post on InstagramThe best time to post on Instagram, by three studies that contradict each other. All three tables of days and hours, and how to find your own window.Times, sizes, limitsHow to use Pinterest TrendsPinterest Trends publishes two years of search, save and shopping data by country. What each section shows, and how the 0 to 100 index really works.Times, sizes, limitsThe best time to post on FacebookThe best time to post on Facebook, by two studies that disagree: Buffer's 14 million posts say mornings, Sprout Social says 12 to 8 p.m. Both tables in full.Who sees whatDoes Facebook notify screenshots?Does Facebook notify screenshots? Not for posts, stories or Reels. Messenger does notify everyone in an end to end encrypted chat, if it detects the capture.Times, sizes, limitsHow long can Instagram Reels be?How long can Instagram Reels be? Up to 20 minutes, though Reels over 3 minutes are not recommended to new audiences. Plus size, cover and frame rate.Posting and ReelsInstagram hashtags for ReelsInstagram hashtags for Reels are capped at five per post. What the five should be, where hashtags still help, and what replaced the old list of thirty.Posting and ReelsInstagram carousel: sizes, limits and slide oneAn Instagram carousel holds up to 20 photos and videos in one post. One orientation applies to all, captions can be per slide, and videos are not Reels.Posting to TikTokFinding popular TikTok songsAny list of popular TikTok songs is wrong within weeks. Here is how to find what is rising today, plus the licensing rule that stops most brands using it.Times, sizes, limitsThe best time to post on YouTubeThe best time to post on YouTube: 40.2 million uploads say the best day beats a channel average by 3.5%, and the hour barely moves views by day 30.Posting and ReelsFinding trending songs on InstagramTrending songs on Instagram are often unusable by a brand: the licensed library is personal use only, and some business accounts cannot open it.Who sees whatHow to clear cache on InstagramHow to clear cache on Instagram: on Android, Settings, Apps, Instagram, Storage, Clear cache. On iPhone there is no cache button, so offload or reinstall.Posting to TikTokFinding trending TikTok hashtagsTrending TikTok hashtags come from TikTok's own browser, by country and week. How to read it, what the numbers mean, and why a copied list is worthless.Instagram storiesHow long do Instagram stories last?How long do Instagram stories last? 24 hours. The viewer list lasts 48 hours, a deleted story 30 days, insights two years, and highlights until removed.Times, sizes, limitsThe best time to post on social mediaThe best time to post on social media, from the 2026 studies: midweek and midday overall, and where Instagram, TikTok, Facebook and YouTube differ by day.Posting and ReelsHow to post multiple photos on InstagramHow to post multiple photos on Instagram: tap POST, then SELECT MULTIPLE, and pick up to 20. The crop applies to all of them. Phone, computer and stories.Times, sizes, limitsThe Twitter character limit on XThe Twitter character limit is 280 on X, but not every character counts as one. Emoji count as two, any link counts as 23, and Premium posts run to 25,000.Posting and ReelsHow to schedule Instagram postsHow to schedule Instagram posts in the app: More options, Schedule this post. Up to 25 a day, 30 days ahead, public accounts only. Plus the desktop steps.Posting to TikTokHow to make a slideshow on TikTokHow to make a slideshow on TikTok: tap Add post, tap Photo, then Upload, and pick up to 35 photos. Sound, text and covers, plus what a slideshow does best.Posting and ReelsWhat Instagram feed meansInstagram feed meaning: the scroll of posts from accounts you follow, plus suggested posts and ads. The signals Instagram names, and how to change it.
Why these exist

Sourced, not repeated.

Running an account well means constantly checking how the platforms behave: what sends a notification, what other people can see, where the limits are.

Most answers online are copied from other answers, and some of them were true years ago. So every claim here names the platform page it came from, and anything those pages do not document is held back for a test on two of our own accounts, one on iPhone and one on Android. Those tests have not been run yet, and each guide says so.

When a platform changes, we test again and say what changed. If you find something that is wrong or out of date, write to [email protected].

How a guide is built.

Every page follows the same order, so you always know where the answer is.

PartWhat is in it
The answerFirst sentence, in plain words. Yes, no, or the number.
The tableThe answer split by format or device, because "it depends" is usually the honest version.
The stepsNumbered, for iPhone, Android and desktop. Screenshots from our own test accounts go in when the test is run.
The exceptionsThe cases where the rule breaks: disappearing messages, business accounts, older app versions.
How we will test thisThe test that is planned, then the devices, app versions and date once it has been run.
QuestionsThe ten things people ask next, answered briefly.
Questions

About the guides.

Are the guides free?

Yes. There is no signup, no paywall and no email gate.

How often are they updated?

Each guide is tested again every quarter, and sooner when readers report a change. Trend lists are updated monthly.

Why does an agency publish these?

Because we have to check how the platforms behave anyway, and writing it down properly is useful to more people than us.

Can I reuse a table or a screenshot?

Yes. Quote what you need and link to the page you took it from.

Do you cover YouTube, LinkedIn or Pinterest?

Not yet. We write about the platforms we run every day first, which are Instagram and TikTok, with Facebook where the same question comes up.

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