PostEverywhere Threads API Guide

PostEverywhere API reference for Threads: reply controls, auto first comments, media rules and request examples.

Publish text posts, image posts, and video posts to Threads (by Meta). PostEverywhere handles Threads' Publishing API to create posts with reply controls, first comments, and media attachments through a single call. For a general overview of all supported platforms, see the Introduction.

Connect your Threads account to PostEverywhere

Connect Threads from the dashboard with OAuth, or headlessly from code: mint a connect link and hand it to the account owner - no dashboard session needed. Both flows are covered in Connecting Accounts.

What you can post to Threads

Content Type	Media Required	Description
Text post	None	Plain text post, up to 500 characters.
Image post	Image(s)	Post with one or more attached images.
Video post	Video (MP4)	Post with a single video attachment.

Threads is designed for short-form text conversations. Posts are limited to 500 characters, making concise writing essential.

Threads-specific options in the API

Use the platform_content.threads object to customise your Threads post:

{
  "platform_content": {
    "threads": {
      "content": "Threads post (max 500 chars)",
      "settings": {
        "replyControl": "everyone",
        "firstComment": "First comment text"
      }
    }
  }
}

Settings Reference

Setting	Type	Default	Description
`content`	string	N/A	Override the default text with a Threads-specific version. Max 500 characters.
`settings.replyControl`	string	`"everyone"`	Who can reply to this post. See values below.
`settings.firstComment`	string	N/A	Text posted as the first reply after publishing.

Reply Controls

Value	Description
`everyone`	Anyone on Threads can reply.
`following`	Only accounts you follow can reply.
`mentioned`	Only accounts mentioned in the post can reply.

Publish to Threads: a working request

Schedule a Threads Text Post

curl -X POST https://app.posteverywhere.ai/api/v1/posts \
  -H "Authorization: Bearer $POSTEVERYWHERE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Default text for other platforms",
    "account_ids": [2295],
    "scheduled_for": "2026-04-15T12:00:00Z",
    "timezone": "America/New_York",
    "platform_content": {
      "threads": {
        "content": "Hot take: the best social media strategy is being genuinely helpful.\n\nNo growth hacks. No engagement bait. Just answer questions and share what you know.\n\nAgree or disagree?",
        "settings": {
          "replyControl": "everyone"
        }
      }
    }
  }'

Schedule a Threads Post with Image and First Comment

curl -X POST https://app.posteverywhere.ai/api/v1/posts \
  -H "Authorization: Bearer $POSTEVERYWHERE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Our new feature just shipped!",
    "account_ids": [2295],
    "media_ids": ["e1f2a3b4-c5d6-7890-1234-ef0123456789"],
    "scheduled_for": "2026-04-15T18:00:00Z",
    "timezone": "UTC",
    "platform_content": {
      "threads": {
        "content": "We just shipped bulk scheduling to PostEverywhere.\n\nSchedule up to 50 posts in a single API call.\n\nFull details below:",
        "settings": {
          "replyControl": "everyone",
          "firstComment": "Docs: https://posteverywhere.ai/docs/quick-start\n\n7-day trial, cancel anytime."
        }
      }
    }
  }'

Schedule a Restricted-Reply Announcement

curl -X POST https://app.posteverywhere.ai/api/v1/posts \
  -H "Authorization: Bearer $POSTEVERYWHERE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Scheduled maintenance notice",
    "account_ids": [2295],
    "platform_content": {
      "threads": {
        "content": "Scheduled maintenance tonight 11pm-1am ET.\n\nAll systems will be back online by 1am.\n\nFollow @posteverywhere for updates.",
        "settings": {
          "replyControl": "mentioned"
        }
      }
    }
  }'

Threads limits: characters, media and video

Requirement	Limit
Post text length	500 characters
Image formats	JPEG, PNG, WebP, HEIC
Image max file size	20 MB
Video format	MP4 (H.264)
Video max file size	1 GB
Video duration	Up to 5 minutes
Recommended image ratio	1:1 (square), 4:5 (portrait) or 9:16
Links in post	Supported (auto-previewed by Threads)

Getting better results on Threads

Write for conversation. Threads is built for dialogue. Posts that ask questions, share opinions, or invite debate get significantly more engagement than announcements. End with a question or a take that people want to respond to.
Use replyControl strategically. Set replies to "mentioned" for announcements where you do not want noise (maintenance notices, official statements). Use "everyone" for posts designed to spark conversation.
Keep it under 500 characters. Unlike other platforms where longer posts perform well, Threads rewards brevity. Get to the point quickly. If you need more space, use firstComment to add context without bloating the main post.

Common questions about posting to Threads

Can I attach images or video to a Threads post?

Yes. Upload your media using the Upload Media endpoint, then pass the returned UUID in the media_ids array in your Create Post request. Threads supports images (JPEG, PNG, WebP, HEIC) up to 20 MB and video (MP4) up to 1 GB and 5 minutes long.

How do I restrict replies on a Threads post?

Set settings.replyControl in the platform_content.threads object. Options are "everyone" (default), "following" (only accounts you follow), or "mentioned" (only accounts mentioned in the post). Use "mentioned" for announcements where you want to limit noise.

What is the character limit for Threads posts?

Threads posts are limited to 500 characters. Unlike LinkedIn or Facebook where longer posts perform well, Threads rewards brevity. If you need more space, use the firstComment setting to add context or links in a reply posted automatically after publishing.

X (Twitter) -- similar short-form text post format and conversational style
Instagram -- owned by Meta, visual-first companion platform
LinkedIn -- longer-form professional text posts

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