Schedule and automate Threads posts with Late API - Text, images, videos, carousels, and thread sequences

Quick Reference

Property	Value
Character limit	500
Images per post	10 (carousel)
Videos per post	1
Image formats	JPEG, PNG, WebP, GIF
Image max size	8 MB (auto-compressed)
Video formats	MP4, MOV
Video max size	1 GB
Video max duration	5 minutes
Post types	Text, Image, Video, Carousel, Thread sequence
Scheduling	Yes
Inbox (Comments)	Reply + delete + hide only (add-on)
Inbox (DMs)	No
Analytics	Limited

Threads has a 500 character limit. This is the #1 failure -- users cross-posting from LinkedIn (3,000), Facebook (63,000), or even Instagram (2,200) captions will fail. Use customContent to provide a shorter Threads version.

Threads is connected to your Instagram account. You must have an Instagram Business or Creator account with Threads enabled. Losing Instagram access means losing Threads.

Additional requirements:

Connected via Instagram authentication (same Facebook app)
If your Instagram account is restricted, Threads posting fails too
Rate limit: 250 API-published posts per 24-hour window

Quick Start

Post to Threads in under 60 seconds:

const { post } = await late.posts.createPost({
  content: 'Sharing some thoughts on building in public',
  platforms: [
    { platform: 'threads', accountId: 'YOUR_ACCOUNT_ID' }
  ],
  publishNow: true
});
console.log('Posted to Threads!', post._id);

result = client.posts.create(
    content="Sharing some thoughts on building in public",
    platforms=[
        {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    publish_now=True
)
post = result.post
print(f"Posted to Threads! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Sharing some thoughts on building in public",
    "platforms": [
      {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    "publishNow": true
  }'

Content Types

Text Post

Threads is one of the few platforms that supports text-only posts -- no media required. Up to 500 characters.

const { post } = await late.posts.createPost({
  content: 'Hot take: the best API is the one with the best docs.',
  platforms: [
    { platform: 'threads', accountId: 'YOUR_ACCOUNT_ID' }
  ],
  publishNow: true
});
console.log('Text post created!', post._id);

result = client.posts.create(
    content="Hot take: the best API is the one with the best docs.",
    platforms=[
        {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    publish_now=True
)
post = result.post
print(f"Text post created! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Hot take: the best API is the one with the best docs.",
    "platforms": [
      {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    "publishNow": true
  }'

Image Post

A single image with an optional caption.

const { post } = await late.posts.createPost({
  content: 'New office setup is looking great',
  mediaItems: [
    { type: 'image', url: 'https://cdn.example.com/office.jpg' }
  ],
  platforms: [
    { platform: 'threads', accountId: 'YOUR_ACCOUNT_ID' }
  ],
  publishNow: true
});
console.log('Image post created!', post._id);

result = client.posts.create(
    content="New office setup is looking great",
    media_items=[
        {"type": "image", "url": "https://cdn.example.com/office.jpg"}
    ],
    platforms=[
        {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    publish_now=True
)
post = result.post
print(f"Image post created! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "New office setup is looking great",
    "mediaItems": [
      {"type": "image", "url": "https://cdn.example.com/office.jpg"}
    ],
    "platforms": [
      {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    "publishNow": true
  }'

Video Post

A single video with an optional caption. Max 1 GB, up to 5 minutes long.

const { post } = await late.posts.createPost({
  content: 'Behind the scenes of our latest product launch',
  mediaItems: [
    { type: 'video', url: 'https://cdn.example.com/launch.mp4' }
  ],
  platforms: [
    { platform: 'threads', accountId: 'YOUR_ACCOUNT_ID' }
  ],
  publishNow: true
});
console.log('Video post created!', post._id);

result = client.posts.create(
    content="Behind the scenes of our latest product launch",
    media_items=[
        {"type": "video", "url": "https://cdn.example.com/launch.mp4"}
    ],
    platforms=[
        {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    publish_now=True
)
post = result.post
print(f"Video post created! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Behind the scenes of our latest product launch",
    "mediaItems": [
      {"type": "video", "url": "https://cdn.example.com/launch.mp4"}
    ],
    "platforms": [
      {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    "publishNow": true
  }'

Carousel

Up to 10 images in a single swipeable post.

const { post } = await late.posts.createPost({
  content: 'Product launch day! Here are all the new features:',
  mediaItems: [
    { type: 'image', url: 'https://cdn.example.com/feature1.jpg' },
    { type: 'image', url: 'https://cdn.example.com/feature2.jpg' },
    { type: 'image', url: 'https://cdn.example.com/feature3.jpg' }
  ],
  platforms: [
    { platform: 'threads', accountId: 'YOUR_ACCOUNT_ID' }
  ],
  publishNow: true
});
console.log('Carousel posted!', post._id);

result = client.posts.create(
    content="Product launch day! Here are all the new features:",
    media_items=[
        {"type": "image", "url": "https://cdn.example.com/feature1.jpg"},
        {"type": "image", "url": "https://cdn.example.com/feature2.jpg"},
        {"type": "image", "url": "https://cdn.example.com/feature3.jpg"}
    ],
    platforms=[
        {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    publish_now=True
)
post = result.post
print(f"Carousel posted! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "content": "Product launch day! Here are all the new features:",
    "mediaItems": [
      {"type": "image", "url": "https://cdn.example.com/feature1.jpg"},
      {"type": "image", "url": "https://cdn.example.com/feature2.jpg"},
      {"type": "image", "url": "https://cdn.example.com/feature3.jpg"}
    ],
    "platforms": [
      {"platform": "threads", "accountId": "YOUR_ACCOUNT_ID"}
    ],
    "publishNow": true
  }'

Thread Sequence

Create connected posts (root + replies) using threadItems. The first item is the root post and subsequent items become replies in order. Each item can have its own text and media.

const { post } = await late.posts.createPost({
  platforms: [{
    platform: 'threads',
    accountId: 'YOUR_ACCOUNT_ID',
    platformSpecificData: {
      threadItems: [
        {
          content: 'Here is a thread about API design',
          mediaItems: [{ type: 'image', url: 'https://cdn.example.com/cover.jpg' }]
        },
        { content: '1/ First, let us talk about REST principles...' },
        {
          content: '2/ Authentication is crucial. Here is what we recommend...',
          mediaItems: [{ type: 'image', url: 'https://cdn.example.com/auth-diagram.jpg' }]
        },
        { content: '3/ Finally, always version your API! /end' }
      ]
    }
  }],
  publishNow: true
});
console.log('Thread posted!', post._id);

result = client.posts.create(
    platforms=[{
        "platform": "threads",
        "accountId": "YOUR_ACCOUNT_ID",
        "platformSpecificData": {
            "threadItems": [
                {
                    "content": "Here is a thread about API design",
                    "mediaItems": [{"type": "image", "url": "https://cdn.example.com/cover.jpg"}]
                },
                {"content": "1/ First, let us talk about REST principles..."},
                {
                    "content": "2/ Authentication is crucial. Here is what we recommend...",
                    "mediaItems": [{"type": "image", "url": "https://cdn.example.com/auth-diagram.jpg"}]
                },
                {"content": "3/ Finally, always version your API! /end"}
            ]
        }
    }],
    publish_now=True
)
post = result.post
print(f"Thread posted! {post['_id']}")

curl -X POST https://getlate.dev/api/v1/posts \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "platforms": [{
      "platform": "threads",
      "accountId": "YOUR_ACCOUNT_ID",
      "platformSpecificData": {
        "threadItems": [
          {
            "content": "Here is a thread about API design",
            "mediaItems": [{"type": "image", "url": "https://cdn.example.com/cover.jpg"}]
          },
          {
            "content": "1/ First, let us talk about REST principles..."
          },
          {
            "content": "2/ Authentication is crucial. Here is what we recommend...",
            "mediaItems": [{"type": "image", "url": "https://cdn.example.com/auth-diagram.jpg"}]
          },
          {
            "content": "3/ Finally, always version your API! /end"
          }
        ]
      }
    }],
    "publishNow": true
  }'

Media Requirements

Images

Property	Requirement
Max images	10 per post (carousel)
Formats	JPEG, PNG, WebP, GIF
Max file size	8 MB per image (auto-compressed)
Recommended	1080 x 1350 px (4:5 portrait)

Aspect Ratios

Ratio	Dimensions	Notes
4:5	1080 x 1350 px	Portrait, recommended
1:1	1080 x 1080 px	Square
16:9	1080 x 608 px	Landscape

Videos

Property	Requirement
Max videos	1 per post
Formats	MP4, MOV
Max file size	1 GB
Max duration	5 minutes
Aspect ratio	9:16 (vertical), 16:9 (landscape), 1:1 (square)
Resolution	1080p recommended
Codec	H.264
Frame rate	30 fps recommended
Audio	AAC, 128 kbps

Platform-Specific Fields

All fields go inside platformSpecificData on the Threads platform entry.

Field	Type	Description
`threadItems`	Array<{content, mediaItems?}>	Creates a thread sequence. First item is the root post, subsequent items become replies in order. Each item can have its own `content` (string) and optional `mediaItems` (array of media objects).

Media URL Requirements

These do not work as media URLs:

Google Drive -- returns an HTML download page, not the file
Dropbox -- returns an HTML preview page
OneDrive / SharePoint -- returns HTML
iCloud -- returns HTML

Test your URL in an incognito browser window. If you see a webpage instead of the raw image or video, it will not work.

Threads uses the same media infrastructure as Instagram. Media URLs must be:

Publicly accessible (no authentication required)
Returning actual media bytes with the correct Content-Type header
Not behind redirects that resolve to HTML pages

WebP images may fail -- use JPEG or PNG for the most reliable results.

Images above 8 MB are auto-compressed. Original files are preserved.

Analytics

Requires Analytics add-on

Available metrics via the Analytics API:

Metric	Available
Impressions	✅
Likes	✅
Comments	✅
Shares	✅
Views	✅

const analytics = await late.analytics.getAnalytics({
  platform: 'threads',
  fromDate: '2024-01-01',
  toDate: '2024-01-31'
});
console.log(analytics.posts);

analytics = client.analytics.get(
    platform="threads",
    from_date="2024-01-01",
    to_date="2024-01-31"
)
print(analytics["posts"])

curl "https://getlate.dev/api/v1/analytics?platform=threads&fromDate=2024-01-01&toDate=2024-01-31" \
  -H "Authorization: Bearer YOUR_API_KEY"

What You Can't Do

These features are not available through the Threads API:

Create polls
Use GIF search
Edit posts after publishing
See who liked or reposted
Create quote posts
Post new top-level comments (reply-only)
Like or unlike comments
Send DMs

Common Errors

Threads has a 14.5% failure rate across Late's platform (7,705 failures out of 53,014 attempts). Here are the most frequent errors and how to fix them:

Error	Meaning	Fix
"Param text must be at most 500 characters long."	Post exceeds the 500 character limit	Shorten to 500 characters. Use `customContent` for cross-platform posts so each platform gets its own version.
"Media download has failed. The media URI doesn't meet our requirements." (2207052)	Threads cannot fetch media from the provided URL	URL must return actual media bytes, not an HTML page. WebP may fail -- use JPEG or PNG instead.
"Instagram account is restricted." (2207050)	The linked Instagram account is restricted	Check your account status on Instagram. Resolve any policy violations before retrying.
"Publishing failed due to max retries reached"	All publishing retries were exhausted	This is usually temporary. Wait a few minutes and retry manually.

Inbox

Requires Inbox add-on — Build: +$10/mo · Accelerate: +$50/unit · Unlimited: +$1,000/mo

Threads supports comment management through the unified Inbox API. Threads does not have direct messaging.

Comments

Feature	Supported
List comments on posts	✅
Post new comment	❌
Reply to comments	✅
Delete comments	✅
Like/unlike comments	❌
Hide/unhide comments	✅

Limitations

No DMs - Threads API does not support direct messages
No comment likes - Threads API does not support liking comments
Reply-only - Cannot post new top-level comments, only replies

See Comments API Reference for endpoint details.

Connect Threads Account - Via Instagram authentication
Create Post - Post creation and scheduling
Upload Media - Image and video uploads
Analytics - Performance metrics
Comments - Reply to comments