Check your accounts first
No app can post for you until these are in place:
- Instagram needs a professional account, creator or business, which is a free switch in Instagram's settings and keeps your followers.
- Facebook needs a Page, because no outside app can post to a personal profile.
- YouTube works with any channel, though setting your own thumbnail needs a verified phone number first.
- TikTok works with the account you already have.
Shoot it tall
If the video is going to all four, film it vertical, 9:16, the way you already hold your phone.
TikTok is built around tall video, and a wide one plays there as a thin strip across the middle of the screen.
Instagram shows a short tall video as a Reel, and YouTube turns a tall video of three minutes or less into a Short.
Wide still has its place, for a long tutorial or anything made for YouTube's main page.
If that's what you made, send it to YouTube and Facebook and leave TikTok out.
How long
Instagram and Facebook take Story videos from 3 to 60 seconds, and a Facebook Story has to be tall.
A YouTube Short can run up to three minutes.
Anything longer is a regular YouTube video, which only means it stays out of the Shorts feed.
One caption for four audiences
The words can be shared too, as long as you write them for the strictest platform.
- Instagram stops a caption at 2,200 characters.
- YouTube wants a title of its own, up to 100 characters, with the description under it, up to 5,000.
- On Instagram and TikTok only the first line or two show before "more", so the first line has to work on its own.
- A link typed into an Instagram or TikTok caption can't be tapped, while YouTube and Facebook turn it into a real link.
So open with the point of the video and put the details after it.
A few hashtags that describe the video do more than a long block of popular ones.
End with the address of your link-in-bio page. People can tap it on YouTube and Facebook, and on Instagram and TikTok it's the same address they'll find in your bio.
Upload the clean file
A common shortcut is to post on TikTok first, save the video from there, and upload that copy everywhere else.
That copy carries TikTok's watermark, and Instagram said in 2021 that it makes Reels with another app's logo or watermark harder to find.
Send every platform the file from your phone or your editor instead.
And send each video to YouTube only once.
A feed moves on from yesterday's post, but a channel is a library, and the same video sent twice sits there twice.
Same moment, or spread out?
Sending to all four at the same moment is fine.
Someone who follows you on two of them sees the video twice, and that's rarely a problem.
The time of day matters more.
If most of your audience lives in one country, post when they're off work.
If it's spread around the world, 14:00 UTC is a fair middle: after lunch in London, morning in New York, late evening in Manila.
It's when Tublish's own posts go out.
Doing it in one send with Tublish
Here is the same send in Tublish:
- Connect each platform once, on the Platforms screen.
- Open Videos → Upload a video and pick the shape, tall or wide.
- Tick where it goes, from the platforms that take that shape.
- Add the file, a title and a description, which YouTube keeps apart and the others join into one caption.
- Send it now, or pick a day and a time and let it wait in Tublish.
If the words are too long for one of the platforms, the screen says so before anything goes out, instead of cutting them.
Afterwards, the Upload log shows what each platform answered.
For Instagram and Facebook you can choose A Story instead of a post: the video alone, with no words, gone after 24 hours.
Send the video as a post today and as a Story tomorrow, and the same film gets a second look.
The free plan connects two platforms, and sending to all four takes a paid plan.