API Reference

LinkedIn API

LinkedIn's Marketing API requires partner program approval, complex URN-based auth, and separate endpoints for each content type. Zernio handles all of that with one POST for text, images, videos, and documents.

Get API Key Full Documentation

Quick Start

1.
Get API Key
Sign up for free and get your API key in seconds.
2.
Connect Account
Use our OAuth flow to connect LinkedIn accounts.
3.
Start Posting
Make API calls to post content to LinkedIn.

Post to LinkedIn

JavaScript

const response = await fetch('https://zernio.com/api/v1/posts', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    content: 'Excited to announce our new API! 🚀\n\nWe just launched...',
    mediaItems: [{ type: 'image', url: 'https://example.com/announcement.png' }],
    platforms: [{
      platform: 'linkedin',
      accountId: 'acc_abc123'
    }],
    publishNow: true
  })
});

const post = await response.json();
console.log(post.post._id); // '65f1c0a9e2b5af0012ab34cd'

LinkedIn Endpoints

POST/v1/posts

Create or schedule a LinkedIn post (text, image, video, or document)

GET/v1/posts/{id}

Get status and details of a LinkedIn post

DELETE/v1/posts/{id}

Cancel a scheduled LinkedIn post

GET/v1/profiles

List all connected LinkedIn profiles and pages

View full API reference →

Media Requirements

Type	Format	Max Size	Notes
Image	PNG, JPEG, GIF	8 MB	1200x627 recommended
Video	MP4	5 GB	3 sec - 10 min duration
Document	PDF	100 MB	Up to 300 pages
Link Preview	URL + metadata	Title: 200 chars	Auto-generated rich preview card

Zernio automatically transcodes and optimizes media for LinkedIn's requirements.

API Limits

LinkedIn's API has daily limits based on your app tier. Zernio manages rate limits automatically, queuing posts when limits are approached.

Zernio handles all rate limiting automatically. We queue and retry requests as needed.

Features

✓Post to personal profiles and company pages
✓Schedule posts for optimal engagement
✓Support for images, videos, and documents
✓Link previews with rich metadata cards
✓Multi-account management
✓Webhook notifications for post status
✓Visibility controls (public/connections)

Response Example

Response

JSON

{
  "post": {
    "_id": "65f1c0a9e2b5af0012ab34cd",
    "status": "published",
    "content": "Excited to announce our new API! 🚀\n\nWe just launched...",
    "platforms": [{
      "platform": "linkedin",
      "accountId": { "_id": "acc_abc123", "username": "acme-corp" },
      "status": "published",
      "platformPostId": "urn:li:share:7012345678901234567",
      "platformPostUrl": "https://linkedin.com/feed/update/urn:li:share:7012345678901234567"
    }],
    "publishedAt": "2025-01-10T10:30:00Z",
    "createdAt": "2025-01-10T10:29:55Z"
  },
  "message": "Post published successfully"
}

Start building with LinkedIn API

Free tier available · No credit card required · 99.97% uptime

Get Free API Key Read Documentation →