I was creating some graphics for a client and had to search for this data, I thought you might find it useful for creating your own LinkedIn graphics.
Replace that default background now and put in something branded.
Profile Images
The profile photo is important as it helps to differentiate you from the rest and show your image.
>>Recommended size: 400px x 400px
>>Minimum dimension: 130px x 130px
Background Images
This image appears behind the profile picture. With this photo you can reinforce your brand’s image.
>> Size: 1584px x 396px
Include an image related to your sector or one of yourself in a successful work situation like delivering a speech, working with clients, in your office, etc.
Here is a sample from one of our brand books.
Images on Your Post
You can publish content as you do it on other social networks. If your post includes an image, the best dimension should be:
>> Size: 520px x 320px
Video sizes on Your Post
Videos formats accepted: ASF, AVI, FVL, MPEG, MKV, MOV and WebM.
>>Video sizes: Between 75 KB and 5 GB.
>>Duration: Between 3 seconds and 10 minutes.