Video posted to TikTok, Instagram and YouTube with PostWire

Video posted to TikTok, Instagram and YouTube with PostWire

An n8n workflow that takes one idea and one video link. PostWire writes a caption for each network, then publishes the video to TikTok, Instagram and YouTube in a single request.

What is inside

• workflow.json: the workflow as n8n exports it, eight nodes: four that do the work and four sticky notes. It holds no credential.
• README.md: these notes.

What we changed from the original copy

• The notes are rewritten. The long one said the free PostWire plan allows 30 posts a month. PostWire's pages, read on 12 November 2026, give the Free plan 10 posts a month, two networks per post and about 20 AI drafts a month.
• The note on step 2 said YouTube drafts carry a title and tags. PostWire's AI writing page says a draft is { text }, with thread or first_comment on some networks, so the note now says only that each draft holds the text.
• The API key line in the notes is a placeholder: Bearer <YOUR_POSTWIRE_API_KEY>.
• The two HTTP Request nodes name a Header Auth credential but link none, so nothing else needed removing.
• Nothing else.

Before you start

• An n8n instance, on n8n Cloud or your own server.
• A PostWire account with TikTok, Instagram and YouTube connected, and an API key. Its keys start with pw_live_.
• A public link to a video file. PostWire's API takes a video_url, and its docs say YouTube needs one.

Set it up

1. In n8n, create a workflow, open its menu and choose Import from File. Pick workflow.json.
2. Create a Header Auth credential with the name Authorization and the value Bearer <YOUR_POSTWIRE_API_KEY>, with your own key in place of the placeholder.
3. Select that credential in Write a native caption per platform and in Publish to every connected account.
4. Open Your idea, video and platforms and enter your idea, the video link, the networks and the voice.
5. Click Test workflow.

How a run goes

1. When you click Test workflow starts the run by hand.
2. Your idea, video and platforms sets idea, video_url, platforms (tiktok, instagram and youtube) and brand_voice.
3. Write a native caption per platform posts prompt, platforms, media_url and brand_voice to PostWire's /api/generate. The answer is a drafts object keyed by network.
4. Publish to every connected account posts platforms, video_url and the drafts as per_platform to /api/post, with TikTok's privacy_level set to SELF_ONLY. PostWire answers with one result per network, and its spec says to check posted and each results[].ok.

Change the look

• The idea and the voice: Your idea, video and platforms.
• The networks: the platforms list in the same node. PostWire's spec lists more, such as LinkedIn, Facebook and Bluesky.
• Who sees the TikTok post: privacy_level in Publish to every connected account. PostWire's spec gives PUBLIC_TO_EVERYONE, FOLLOWER_OF_CREATOR, MUTUAL_FOLLOW_FRIENDS and SELF_ONLY.
• When it runs: swap the manual trigger for a schedule, a feed or a sheet trigger.

Good to know

• The workflow publishes to real accounts as soon as it runs. TikTok starts private, and YouTube's privacy defaults to private too, so check the first posts before you open them up.
• On the Free plan, PostWire sends each post to two networks. The third comes back held with the code networks_per_post. One idea sent to three networks counts as three posts.
• PostWire refuses an identical post for two minutes, which stops a retried step from posting twice.
• YouTube's title defaults to the first line of the text, cut at 100 characters.
• PostWire's terms, read on 12 November 2026, welcome use inside your own workflows and ban spam and deceptive content. You are also bound by each network's own rules.
• This copy was not run against PostWire, TikTok, Instagram or YouTube. PostWire's API spec was read as a document, and no call was made.
• Your idea, the video link and the captions go to PostWire.
• The JSON holds no credential.