LinkedIn’s post limit is 3,000 characters. Its video limit is 3 seconds to 30 minutes, with a file between 75 KB and 500 MB. Its connection and invitation limits are a different story: LinkedIn confirms that limits exist and applies them aggressively, while publishing almost nothing about where they sit.
LinkedIn posting and media limits
| Limit | Value |
|---|---|
| Post text | 3,000 characters |
| Video duration | 3 seconds to 30 minutes |
| Video file size | 75 KB to 500 MB |
| Video format | MP4 |
| Caption file | One per video, English only |
| Headline | 220 characters |
Note: The video figures here were verified against LinkedIn’s Videos API documentation on Microsoft Learn as of September 2026. Platforms change these without notice.
The video upload is multipart, split into 4 MB parts, and the upload URLs expire (LinkedIn’s documentation says typically 30 days from initialisation). None of that matters when you are uploading by hand in the app. It matters a great deal when a scheduling tool queues a video for next month, because the asset has to be uploaded close to publish time rather than at the moment you compose.
For post text, including how LinkedIn truncates in the feed and the separate limits for comments, articles, and headlines, see LinkedIn character limit. The LinkedIn character counter shows the cutoff point as well as the cap.
Where the LinkedIn feed cuts off
3,000 characters is the ceiling. The feed shows roughly the first few lines before a “see more”. LinkedIn also demotes nothing for length, so long posts are viable, but the first two lines carry the entire cost of getting someone to expand.
LinkedIn connection and invitation limits
LinkedIn is the platform where undocumented limits do the most damage, because sales teams run outreach at volume and LinkedIn restricts accounts that do.
What LinkedIn confirms publicly: there is a limit on invitations, it is applied per account, and accounts that are repeatedly marked “I don’t know this person” or that have invitations ignored at a high rate get restricted. What LinkedIn does not publish: the number.
Widely reported community figures put weekly invitation ceilings in the low hundreds for ordinary accounts, with lower effective ceilings for new accounts and accounts with a poor acceptance rate. Those numbers are reported and unofficial. LinkedIn has changed the enforcement more than once, has run it as a weekly rather than daily window, and has applied different treatment to accounts based on history. There is no single correct number to publish.
The signals that appear to drive it:
- Acceptance rate. This is the dominant one on LinkedIn. Invitations that go unanswered or get declined shrink your allowance directly.
- “I don’t know this person” reports. These are the fastest route to a restricted account.
- Account age and profile completeness. New, sparse profiles are throttled harder.
- Automation fingerprints. Browser automation against LinkedIn is against the User Agreement, and detection is not subtle.
The same applies to InMail, connection messages, profile views at volume, and search result quotas: limits exist, LinkedIn enforces them, and the thresholds are not published.
What is safe to automate on LinkedIn
Publishing is. LinkedIn has a documented, official API for posting on behalf of a member or an organisation, and using it is exactly what it exists for. Connecting, messaging, and profile scraping are not: there is no official API for member outreach at volume, which is why every tool that does it works by driving a browser, and why those tools get accounts restricted.
If a tool offers to send connection requests for you, that is the part to be careful about, not the scheduling.
The short version
- Post text: 3,000 characters. Headline: 220.
- Video: 3 seconds to 30 minutes, 75 KB to 500 MB, MP4.
- Video uploads are multipart and the upload URLs expire, so schedulers upload near publish time.
- Invitation and messaging limits exist, are enforced by acceptance rate as much as by volume, and are not published. Reported weekly ceilings are unofficial.
Scheduling LinkedIn posts inside the documented limits
BulkPublish publishes to LinkedIn through the official API for both personal profiles and company pages, and enforces the 3,000-character cap in the composer rather than at publish time. It does not send connection requests or messages, because there is no official API for that and the tools that do it put the account at risk.
Teams that queue a month of LinkedIn content at once usually want approvals in front of it, so a post written three weeks ago gets a second read before it goes out under someone’s own name.