LinkedIn - Postbreeze

Quick reference

Field	Value
Caption limit	3,000 characters
Images per post	1–20
Videos per post	1
PDF documents per post	1
Mixed media	❌ Image OR video, never both
Image formats	JPG, PNG, GIF, WebP, HEIC, HEIF
Video formats	MP4, MOV, AVI, WebM
Document format	PDF
Max image / video size	5 GB
Max document size	100 MB
Post types	Personal, Company, PDF Carousel
First comment	✅ Auto-posts after publish
Account types	LinkedIn Personal + Company Pages

Before you start

LinkedIn ships two distinct multi-image experiences with very different reach. Postbreeze exposes both:

Photo gallery (MultiImage) — 2–20 images in a swipeable gallery. Lighter feed treatment.
Document carousel (PDF) — your images composited into a single PDF that LinkedIn renders as a full-bleed slide deck. Typically 1.5–3× the organic reach of MultiImage posts.

Pick via postAsPdfCarousel: true | false on the platform options. See platform settings → LinkedIn Personal and LinkedIn Company.

Required scopes:

Personal: openid, profile, email, w_member_social, w_member_social_feed.
Company: w_organization_social, r_organization_social, rw_organization_admin, w_organization_social_feed.

The _feed scopes were added in May 2026 for first-comment support. Accounts connected before then need to reconnect — the compose UI shows a banner. For analytics, additional scopes may be required and gated behind LinkedIn’s Marketing Developer Platform review (multi-week process). Posting works without them.

Quick start

Workspace is inferred from your API key — no workspaceId argument. All examples use the flat shape (content + platforms); the nested shape at the bottom is equivalent and accepted by the same endpoint.

SDK

import Postbreeze from "@postbreeze/node";

const postbreeze = new Postbreeze({ apiKey: process.env.POSTBREEZE_API_KEY! });

await postbreeze.posts.create({
  content: "Reflections on our first year — what I'd do differently.",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [{ type: "image", url: "https://cdn.example.com/photo.jpg" }],
  platforms: [{ accountId: "soc_linkedin_…" }],
});

import Postbreeze from "@postbreeze/node";

const postbreeze = new Postbreeze({ apiKey: process.env.POSTBREEZE_API_KEY });

const post = await postbreeze.posts.create({
  content: "Reflections on our first year — what I'd do differently.",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [{ type: "image", url: "https://cdn.example.com/photo.jpg" }],
  platforms: [{
    accountId: "soc_linkedin_…",
    platformOptions: {
      platform: "LINKEDIN_PERSON",
      visibility: "PUBLIC",
    },
  }],
});

For details on mediaItems vs. pre-uploaded mediaIds, see media uploads.

Content types

Personal post

platform: "LINKEDIN_PERSON". Works for text-only, single image, single video, MultiImage gallery (2–20 images), PDF document, or PDF carousel (composited from images).

Company page post

platform: "LINKEDIN_COMPANY". Same supported shapes as Personal. The connected account must be on the workspace whose Company Page the user administers — the OAuth flow fans out one row per Page the user can post to. Company actors always render publicly server-side regardless of visibility.

MultiImage gallery (2–20 images)

Send 2–20 images. Per-image alt text is supported via altText on each mediaItem.

const post = await postbreeze.posts.create({
  content: "5 patterns I see in fast-growing B2B teams 🧵",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [
    { type: "image", url: "https://cdn.example.com/cover.jpg", altText: "Cover slide titled '5 patterns'" },
    { type: "image", url: "https://cdn.example.com/p1.jpg", altText: "Pattern 1 — They write internal memos" },
    { type: "image", url: "https://cdn.example.com/p2.jpg" },
    { type: "image", url: "https://cdn.example.com/p3.jpg" },
    { type: "image", url: "https://cdn.example.com/p4.jpg" },
  ],
  platforms: [{
    accountId: "soc_linkedin_…",
    platformOptions: {
      platform: "LINKEDIN_PERSON",
      visibility: "PUBLIC",
      postAsPdfCarousel: false,
    },
  }],
});

Document carousel (composited from images)

Send 2+ images and postAsPdfCarousel: true. Postbreeze composites the images into a single PDF and uploads as a document — LinkedIn renders it as a swipeable slide deck. pdfCarouselTitle is required and shows under the carousel (≤ 100 chars).

await postbreeze.posts.create({
  content: "5 patterns I see in fast-growing B2B teams 🧵",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [
    { type: "image", url: "https://cdn.example.com/slide1.jpg" },
    { type: "image", url: "https://cdn.example.com/slide2.jpg" },
    { type: "image", url: "https://cdn.example.com/slide3.jpg" },
  ],
  platforms: [{
    accountId: "soc_linkedin_…",
    platformOptions: {
      platform: "LINKEDIN_PERSON",
      visibility: "PUBLIC",
      postAsPdfCarousel: true,
      pdfCarouselTitle: "5 patterns I see",
    },
  }],
});

Real PDF document

Attach an actual PDF — LinkedIn renders it as a swipeable carousel natively. This is separate from postAsPdfCarousel (which composites images into a synthetic PDF); here you’re uploading a real document. Use type: "document" in mediaItems, or pass a med_… id from a presigned PDF upload via mediaIds.

PDFs only work on LinkedIn. Cross-posting a type: "document" item to any non-LinkedIn target returns 400. Send PDFs to LinkedIn accounts only.

await postbreeze.posts.create({
  content: "Our 2026 product strategy in one deck.",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [
    { type: "document", url: "https://cdn.example.com/strategy-deck.pdf" },
  ],
  platforms: [{
    accountId: "soc_linkedin_…",
    platformOptions: { platform: "LINKEDIN_PERSON", visibility: "PUBLIC" },
  }],
});

Video

platform: "LINKEDIN_PERSON" (or LINKEDIN_COMPANY) with a single video mediaItem.

await postbreeze.posts.create({
  content: "Walking through our new onboarding flow.",
  scheduledFor: new Date(Date.now() + 30_000).toISOString(),
  mediaItems: [{ type: "video", url: "https://cdn.example.com/onboarding.mp4" }],
  platforms: [{
    accountId: "soc_linkedin_…",
    platformOptions: { platform: "LINKEDIN_PERSON", visibility: "PUBLIC" },
  }],
});

Media requirements

Images

Property	Requirement
Images per post	1–20
Formats	JPG, PNG, GIF, WebP, HEIC, HEIF
Max file size	5 GB
Aspect ratio	Any (LinkedIn auto-crops to 1.91:1 in Feed)
Per-image alt text	✅ via `altText` on each `mediaItem`
Max alt-text length	1,000 chars

Videos

Property	Requirement
Videos per post	1
Formats	MP4, MOV, AVI, WebM
Max file size	5 GB
Aspect ratio	16:9 to 1:2.4
Codecs	H.264 + AAC
Max resolution	4K

Documents

Property	Requirement
Documents per post	1
Format	PDF
Max file size	100 MB

Platform-specific fields

See platform settings for the canonical schema reference.

Personal — `#linkedin-personal`

Field	Type	Required	Description
`platform`	`"LINKEDIN_PERSON"`	Yes	Discriminator.
`visibility`	`"PUBLIC"` \| `"CONNECTIONS"`	No (default `PUBLIC`)	Connections-only is honored by LinkedIn’s audience filter.
`postAsPdfCarousel`	boolean	No	When true and 2+ images attached, composites them into a PDF and posts as a Document carousel.
`pdfCarouselTitle`	string (≤ 100)	When `postAsPdfCarousel: true`	Title shown under the carousel.

Company — `#linkedin-company`

Field	Type	Required	Description
`platform`	`"LINKEDIN_COMPANY"`	Yes	Discriminator.
`visibility`	`"PUBLIC"` \| `"CONNECTIONS"`	No (default `PUBLIC`)	Kept for shape parity. Company actors always post publicly — server-forced.
`postAsPdfCarousel`	boolean	No	Same as Personal.
`pdfCarouselTitle`	string (≤ 100)	No	Same as Personal.

First comment

Pass firstComment on the platform entry. Postbreeze waits 8 seconds after the main post (LinkedIn enforces a per-member 1-minute throttle on create-actions) and then posts as the same author. Supported on both Personal and Company.

platforms: [{
  accountId: "soc_linkedin_…",
  platformOptions: { platform: "LINKEDIN_PERSON", visibility: "PUBLIC" },
  firstComment: "Full breakdown: https://blog.example.com/patterns",
}]

Limit: 1,250 characters per LinkedIn comment (smaller than the 3,000 caption cap — surface this in your UI).

Analytics

Metric	Available
Likes	✅
Comments	✅
Reshares	✅
Impressions	⚠️ Requires Marketing Developer Platform approval
Click-through rate	⚠️ Requires MDP approval
Reach (unique)	⚠️ Requires MDP approval
Engagement rate	⚠️ Requires MDP approval
Followers (Company)	⚠️ Requires MDP approval

The Postbreeze analytics page detects when these scopes are missing and shows an “approval pending” banner instead of fake zeros.

Common errors

Error	Meaning	Fix
`LI_FIRST_COMMENT_THROTTLED`	Hit the 1-minute per-member create limit	Use the retry button in the post-detail dialog.
`LI_FIRST_COMMENT_SCOPE_MISSING`	Account doesn’t have `w_member_social_feed` (or `w_organization_social_feed`)	Reconnect the account.
`LI_MIXED_MEDIA`	Image + video in the same post	LinkedIn requires one or the other.
`LI_PDF_VIDEO_CONFLICT`	`postAsPdfCarousel: true` with a video attached	Remove the video or set to false.
`LI_PDF_NEEDS_TWO_IMAGES`	`postAsPdfCarousel: true` with only one image	Add at least one more image.
`LI_MULTI_IMAGE_RATE_LIMITED`	Burst uploaded >5 images/sec to the Images API	Postbreeze retries with exponential backoff.
`LI_TOKEN_EXPIRED`	LinkedIn refresh failed	Reconnect.
`LI_CAPTION_TOO_LONG`	> 3,000 chars	Trim.

What you can’t do

❌ Schedule via LinkedIn’s native scheduler
❌ Mix image + video in one post
❌ Multi-video posts (1 video max)
❌ Image-in-first-comment (separate flow, deferred to v2)
❌ Tag specific users via API (you can include @Name in text but no structured tags)
❌ Polls or events
❌ Newsletters
❌ Edit a post after publish
❌ Stories (LinkedIn deprecated these)

Full control: nested shape

The targets / socialAccountId / caption / scheduledAt / mediaIds shape is the original API surface and remains fully supported. Use whichever you prefer — both go to the same POST /api/v1/posts endpoint.

import Postbreeze from "@postbreeze/node";

const postbreeze = new Postbreeze({ apiKey: process.env.POSTBREEZE_API_KEY! });

await postbreeze.posts.create({
  caption: "Reflections on our first year — what I'd do differently.",
  scheduledAt: new Date(Date.now() + 30_000).toISOString(),
  mediaIds: ["med_image_…"],
  targets: [{
    socialAccountId: "soc_linkedin_…",
    platformOptions: {
      platform: "LINKEDIN_PERSON",
      visibility: "PUBLIC",
    },
  }],
});

​Quick reference

​Before you start

​Quick start

​Content types

​Personal post

​Company page post

​MultiImage gallery (2–20 images)

​Document carousel (composited from images)

​Real PDF document

​Video

​Media requirements

​Images

​Videos

​Documents

​Platform-specific fields

​Personal — #linkedin-personal

​Company — #linkedin-company

​First comment

​Analytics

​Common errors

​What you can’t do

​Full control: nested shape

Quick reference

Before you start

Quick start

Content types

Personal post

Company page post

MultiImage gallery (2–20 images)

Document carousel (composited from images)

Real PDF document

Video

Media requirements

Images

Videos

Documents

Platform-specific fields

Personal — `#linkedin-personal`

Company — `#linkedin-company`

First comment

Analytics

Common errors

What you can’t do

Full control: nested shape