The first took me 30-40 minutes, then about 15-20 each. It wasnt bad.

From unpackaging to ready-to-install I'd say a first-timer should allocate about 15-24 hours.

I just assembled and installed an ikea kitchen myself. The order of operation is as follows:
1) assemble boxes
2) install boxes, including panels
3) assemble & install drawers and cabinet doors
4) install plywood tops on base cabinets
5) install countertops and complete finish plumbing
6) install deco strips and plinths

Assembling the boxes is the fastest and easiest part of the whole operation, like ~15-20min per box.

Installing the boxes and panels took a lot of time for me, like 1-2 hours per box, but maybe I'm just slow &/or a perfectionist. Base cabinets were tricky for me partly because my floor & walls are crazy out of level/plumb/square and it took me a while to understand all the implications of that - be sure to understand the topography of the floor before you start. And wall cabs take time as well to get the rails mounted securely and whatnot.

Each drawer takes ~15min and each cabinet door takes ~10min.

Plywood is pretty easy, say ~15min per base cab box.

Then deco strips and plinths took another hour or so per wall & base cab box respectively.

That's what I would have guessed, about an hour per on average.

I'm also in the midst of Ikea cabinet assembly, and here's what I'd suggest.
(I'm assuming that you've checked your order and know that you have everything, or have it on the way from Ikea. In my case, I had to wait for replacements for a few damaged or missing items, and it takes time for them to process your "case" for re-delivery.)

First, I would assemble a tool kit and a box to keep all tools together. That will save you time and frustration. YMMV, but the tools I've found most useful are a small, re-chargeable power screwdriver, a sharp knife for opening boxes and hardware packets, a rubber mallet for tightening sides and bottoms of the cabinets before locking the cams and nailing on the backs, a hammer comfy in your hand, an awl for those places where you have to drive a screw through the melamine surface and there's no predrilled hole. An example is the 30" and wider drawers, where the drawer rails are attached with four screws per side. The narrower drawers are solid with two screws per rail.

Oh, speaking of the backs, every time you go to install one, say out loud to yourself "white side down", and it will keep you from putting it on so that the unfinished side is accidently facing in to the inside. No fun to take a back off after it's nailed down...

You got a great suggestion from Detroit burb above to install the rails while the cab walls are still flat on the table or floor. It's much easier than trying to climb inside later!

Just start with one of your small wall cabs, look at all the directions, and follow them exactly. For my first few cabs, I found it helpful to actually lay out the pieces exactly in the orientation shown in the diagrams. Where you see the graphic of a small hand outline pointing to something in an illustration, take particular heed, as those are critical points for possible error.

You don't have to force anything, so if it isn't going together with ease, stop and recheck all your previous steps.

It is SO easy, you will be able to do it without even referencing the instructions after doing just the first few cabinets. I'd never done them before, and now I'm confident cutting them down to specific sizes I want.

+1 on the power screwdriver!

well it sure sounds easy - thanks everyone! I will save all these tips.

It sounds easy and fun. I wish I knew someone who could use a hand assembling cabinets.

I too have about 21 cabinets. Any rough estimate on how many feet of edge banding I need? My reading says I should choose fastedge banding prefinished in the color Fuji Cherry for my Adel medium brown IKEA color...?

I just had Ikea cabinets put in - about 20 of them. Traemand, the company who I paid had two guys doing the installation. It took them 3 days. They did a lot of things I don't think I would have thought to do. They arrived every day at 8am, left at 4pm and took an hour for lunch. I paid about 3K and they seemed to be very metculous besides being very nice guys who I didn't mind having in my house.

There was a problem with a panel missing, they went and picked it up themselves. Ikea is about 45 minutes from our house.

Best thing is that they made sure I was included in each step of the installation. Though recently had some other contract work done and quality of work was good but quality of communication was very poor. This was a much better experience - wish all contractors were so careful to include the homeowner in the process.

The way I understand how Traemand works, they subcontract out the work so I guess I was just lucky. I could have just as easily got some guys who were not so great.

I had a contractor estimate me $2870 to install my 21 cabinets...is that high or a good price?

Assembled and installed, it's terrific.

Too low. Even a box store sub gets more than that just to install that many cabinets. And they don’t have to put them together.

It took us 2 weeks to do an entire average kitchen - upper, lower and 3 pantry cabinets. Then additional time to wait for delivery on pieces that were backordered - all total 3 weeks. Take your time and make sure the rails are level. We ended up hiring a carpenter to come and do the finish for us as cutting and installing the filler pieces requires a saw and some precision to get it just right. Knee pads are also a good idea if you're building cabinets on the floor. A little caulk at the seems really helps finish them out. Kitchen turned out beautiful!