The automatic numbering of artboards is not correct.
21 does not exist, while 22 exists two times.
Though when testing to save the specific artboards, the "first 22" saves as 21, therefore the underlaying logic is working.
Same problem with 25/26, 27/28, 29/30
This time I only tested until 30. I don't know if I've seen it before.

There is a bug when creating multiple artboards or adding multiple artboards; causing the numbering to be off.

Illustrator 27.4.1
Mac OsX Monterey 12.4

I automatically get 21, 22, 24, 24, 25…
instead of 21, 22, 23, 24, 25…
The artboard n23 is missing

Today I noticed that if this error started, it affects all other files too. Restarting Illustrator fixes it

Please don't mind this user with the hateful speech below. I think we all share this pain because of this problem, and understand the rage it often invokes. Comments like this are not pretty, but they are good signals. But please restrain yourself from calling people 'losers'.

You all losers think that adobe is going to fix this problem. This particular problem is glued in AI since 2019. They don't want to fix it. Wake up. We are all losers for paying this ''company''.

When I duplicate an artboard, it is duplicated with the same name as the previous one.

I have to change the name manually to export all the artboards otherwise it skips the duplicated artboards. When will it be fixed?

I may have find a way to replicate the bug : I just made two different files with large numbers of artboards, and I noticed that if I add artboards too fast, the bug happen. If I add some (with the "+" button) on a steady rythm, but not too fast, it doesn't occur.

When I copy artboards and make new artboards the automatic numbering of the artboards goes wrong. And when exporting an artboard you can't export the right artboard.

MacOS Ventura 13.0.1
Illustrator 26.5

When displaying a large number of artboards on the same screen, numbers don't follow (see screen capture, artboard 70 dos not appear, the 71 is doubled. When exporting by asrtboards, the first 71 does not get exported.

I created an A4 artboard then proceeded to add artboards in a side by side print layout but when I get to artboard 13, the next one added is 15 and the next after that is also 15, it then goes to 16? Very strange?

I have just experienced the same thing. and posted about it in forum and linked to this post as being similar. not causing me any real issues but I thought it might be useful to know that had same thing happen. I have been using Illustrator for 20+ years never noticed before.

I was just was creating artboards for project and I noticed the numbering system has replaced 7 with an 8.

I added a couple of extra layers and seems to add them fine with numbering. not urgent. Just highlighting it as seems another user has also had similar issue. https://illustrator.uservoice.com/forums/601447-illustrator-desktop-bugs/suggestions/39220252-artboards-with-the-same-number

Artboard number sequencing is not correct post 33, Artboard 34 is missing

The software starts skipping random numbers when there are more than 20 art boards. It feels like ai can't count??!!!??

@Amber, sadly, these steps do nothing for me, and their variations too. No skips, no duplicates... You are lucky to be able to keep Ai live for 5 days, without a crash :) But yes, I confirm that it never happens if it was launched recently, and always happens in the heat of an action, with Ai being launched for a while, with a lot of tabs.

Why it often happens at the eights artboard though...
Thanks for the comment, the searches continue.

I have the steps to get this to show up on my computer(Mac). I notice with a different file and was able to get it to happen again with fresh file. My issue was artboard number 8 would be skipped and number 9 would be duplicated.

Starting with a fresh file with three artboards.

-Go into artboard tool
-Delete two of the artboards
-Duplicate the remaining artboard over the the right holding shift and option
-Do this step with the second artboard
-Select the three artboards and duplicate them down holding shift and option
-Repeat the last step and find that what should be artboard 8 is now artboard 9 twice

Something I noticed that if I restarted ai(quit the application) the bug would disappear. I couldn't recreate it then and the file I was working in was fixed. My thought is it might be a combination with having multiple tabs open and have your application open for days on end. When I found this bug I had five tabs open and with two of them needing to be saved(having an * by the file name). I believe ai was opened five days prior without being closed out. I am not a coder so I don't know if this has anything to do with it but this was my experience.

I just got this message from Illustrator when trying to export one specific artboard. I have never seen this message before. The artboard it self is numbered 79, but should be nr 78. I looked at the artboard menu and the info on the artboard and there it is number 78! So it worked for me to export nr 78 but this is a very strange error. Why is this happening?

Created a new document and it still is skipping one number (56) and duplicating one (59)! Is there no bug fix for this 2.5 years later??? If I do the option Lisa mentions, it does export ok but the file itself is still incorrect.

When this happens to me (happens randomly) it is always after I save the original file. A workaround is to export before saving. Another workaround I have found is to 1. select artboard tool 2. select ALL artboards (hold down shift and click each one) 3. click on Artboard Options 4. under the name option, type Artboard 1. This should reset the names of the artboards. 5. Export. Do not save the file first or it reverts back to the incorrect artboard numbers. Hope this helps someone.