Not a direct copy

How to post from X to YouTube

Not directly. YouTube will not accept a text-only post, so a straight copy is impossible — the post has to be rebuilt for YouTube, not forwarded to it.

Side by side

XYouTube
Characters2805,000
Mediaoptionala video (required)
Hashtags1-2 hashtags, zero is fine3-5 hashtags in the description, never more than 15 total
Links in bodysuppress reachfine
Needs platform approvalyesyes

What changes, one by one

YouTube will not accept a text-only post

X posts are frequently text-only. YouTube requires a video on every post, so there is no direct equivalent — you have to attach media before this cross-post is even possible.

You have 4,720 characters you are not using

X caps at 280 characters, YouTube allows 5,000. Posting the short version verbatim wastes the room YouTube gives you to actually explain the thing.

The hashtag rules are not the same

X: 1-2 hashtags, zero is fine. YouTube: 3-5 hashtags in the description, never more than 15 total. Carrying the tag block across is the single most obvious sign of an automated cross-post.

YouTube lets you put the link back in

X penalises links in the body, so posts written for it park the URL elsewhere. On YouTube links in the body are fine — putting it back is free reach.

YouTube needs a title you never wrote

YouTube requires a separate title (max 100 characters). X has no such field, so there is nothing to copy across — it has to be written.

Why copy-paste cross-posting underperforms

X is one hook and nothing else — opinionated, conversational, over in a breath. YouTube is a search engine: the title carries the keyword in the first 40 characters. Those are different jobs, so the same words cannot do both well — and every algorithm here demotes text that obviously was not written for it. The fix is not to skip cross-posting; it is to send a native version to each network.

Publish to both in one call

curl -X POST https://postwire.io/api/post \
  -H "Authorization: Bearer $POSTWIRE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "platforms": ["x", "youtube"],
    "text": "Your post",
    "per_platform": {
      "x": { "text": "The X version" },
      "youtube": { "text": "The YouTube version" }
    }
  }'

PostWire's /api/generate writes those per-platform versions for you from a single prompt, respecting every limit in the table above. From an AI agent it is one MCP tool call.

Do this without writing the post twice

PostWire takes one idea and publishes a version written for each network — the right length, hashtags and format per platform. It also refuses posts that would fail, like a video network with no video, before they are queued.

Free for one brand — 30 posts a month, no card. Starter is $9/month for three brands and 300 posts. There is a REST API and an MCP server if you would rather automate it.

Start free — no card →

Questions people actually ask

Can I cross-post from X to YouTube?
Not directly. YouTube will not accept a text-only post, so a straight copy is impossible — the post has to be rebuilt for YouTube, not forwarded to it.
What is the character limit difference between X and YouTube?
X allows 280 characters and YouTube allows 5,000.
How do I post to X and YouTube at the same time?
With PostWire, one API call publishes to both: POST /api/post with platforms set to ["x","youtube"]. Or one MCP tool call from an AI agent.

Other pairs: YouTube to X · all combinations · which APIs need approval

Picking a tool for this? We compared the ones with a public API side by side in the alternatives guide, prices included.