How many slides are the best for a compelling pitch?

Never needed to pitch. See my website. You will get more ideas. https://artfinitydesign.com/

I think if there are a lot of presentation slides, it will be annoying, 12 slides of important information may be enough.

Stick to 10 20 30 rule for your presentation. It means the following: 1) Your presentation should consist of no more than 10 slides 2) Your presentation should last no longer than 20 minutes 3) The text on each slide should be no lower than 30 points in size

The best is to keep it between 10 to 15 slides. If you go overboard, you lose interest and if you do less than 10, the audience might ask too many follow-up questions because you don't cover all topics. Try Decktopus.com to make sure you have a streamlined pitch deck outline.

If it's truly compelling, try 3. Then mic drop.

Hmmm I'm currently working on a pitch deck that I'll be first sending via email. It has 18 slides, 2 of which include product screenshots and a video. I was following the recommended pitch deck structures by some VCs and tried to be as precise as possible when talking about the product -- really don't think there's an ideal number of slides.

10-12 slides.

15-18 slides.

12 to 20 at max should do the job

Who's the audience mate?

if you are able to make it within 1 pager I believe it is best as for founders as for investors, as you are saving time for both sides