Knowing exactly how many characters you can squeeze into any text field on LinkedIn is going to save you a lot of time and frustration. It's strange that LinkedIn doesn't provide this information in the Help Center so I put it together to help you, here's a comprehensive list of maximum character counts and limits. LinkedIn changes all kinds of things on a daily basis, so please bear that in mind this list is current as of today.
1. NAME: First Name: 20 characters, Last Name: 40 characters.
2. HEADLINE: 120 character limit.
3. SUMMARY: 2,000 character limit.
4. RECOMMENDATION: 3,000 character limit.
5. PUBLISHER Post Headline: 100 maximum characters.
6. PUBLISHER Post Body: 40,000 characters.
7. WEBSITE Anchor Text: 30 maximum characters.
8. WEBSITE URL: 256 maximum characters.
9. VANITY URL: 5-30 characters after ‘www.linkedin.com/in/’ (a)
10. POSITION Title: 100 maximum characters.
11. POSITION Description: 200 character minimum (2000 maximum characters).
12. INTERESTS: 1,000 character limit.
13. ADDITIONAL INFO / Advice For Contacting: 2,000 character limit.
14. PHONE number: 25 character limit. (b)
15. IM (Instant message): 25 character limit. (b)
16. ADDRESS: 1,000 character limit. (b)
17. SKILLS: 80 characters per Skill.
18. COMPANY Name (Overview tab): 100 maximum characters.
19. COMPANY About Us (Overview tab): 200 min / 2,000 max.
20. COMPANY Update (Updates tab): 1,300 characters.
21. CAREER Pages (Life tab): Company Leaders headline: 150 character limit.
22. CAREER Pages (Life tab): Company Leaders description 150 character limit.
23. CAREER Pages (Life tab): Employee Testimonials 400 character limit.
24. CAREER Pages (Life tab): Custom Module title 150 character limit.
25. CAREER Pages (Life tab): Custom Module body 500 character limit.
26. CAREER Pages (Life tab): Custom Module URL label 70 character limit.
27. SHOWCASE Page Name: 100 maximum characters.
28. SHOWCASE Page Description: 75 min / 200 max.
29. UPDATE: 1,300 maximum characters. (c)
30. MESSAGE (InMail): 200 characters (Subject) / 1,900 character limit (Body).
31. GROUP Discussion Title: 200 maximum characters.
32. GROUP Discussion Body (Conversation): 2,000 character limit.
33. GROUP Discussion Comments: 1,000 character limit.
34. LinkedIn TEXT AD Headline: 25 character limit.
35. LinkedIn TEXT AD Message Body: 75 character limit.
36. LinkedIn Direct SPONSORED Content: 160 character limit.
37. Profile ‘PUBLICATION’ Title: 255 character limit.
38. Profile ‘PUBLICATION’ Description: 2,000 character limit.
39. COMMENTS (on an article or a share/post): 1,750 character limit.
40. PUBLISHER, photo/image credit: 250 character limit.
41. INVITATION to CONNECT Message Body: 299 character limit.
(a) Your custom URL can have 5-30 letters or numbers. The only special character you can use is a dash “-“
(b) [14,15,16] Only your 1st degree connections, can see this information.
(c) [Status Update] Though text limit is 1,300 maximum for updates, note that if you select to also post on Twitter from LinkedIn, only the first 280 characters will show on your Twitter post.
A really useful tool which will count your characters for you: lettercount
Unfortunately, the current LinkedIn profile only shows the first 2 lines of your summary, before a reader has to click ‘See more’ to see the full version, my research shows you have approx. 200-250 characters (or 25-42 words) to entice your reader to click. My advice: don’t bore them and get to the point, pique their curiosity asap.