Not a good question to ask here. Unless you know how to test circuits, you could be creating a very hazardous situation. All dimmers are not equal. You need a qualified electrician to test whether or not it is appropriate on every single situation on a case by case basis.

Yes probably; but like Fred said, you need to know how much you can run off of 1 switch; then you need to know how many watts you are pulling out of each recessed can. However, did you need to have a spare box? Just because you want to combine 2 switches, leaving you only 1, it remains because your electrician wired this in a triple (3) box. You would have to put a dummy in the 3rd box.

@ Cathy - wattage is not the issue. There are several more dangerous situations that can occur here. This forum is not the place to express a guess on this subject.

Yes, a standard dimmer is good up to 600 watts.

@ ronny - you do not even know if both switches originate from the same circuit. Please do not make such poor assumptions and try to pass it off as fact.

Both switches are from the same circuit but the wiring is a bit of a mess. The wires are stamped into the switches instead of on the screws and their just seems to be more wires then I can make heads or tails of. I'm not an electrician but it seemed at first easy enough. Any videos online recommended for such work?

You say there are more wires than you can make heads or tails of, and yet you are sure they are on the same circuit?

Why do you want to combine them? Two switches are cheaper than an electrician.

I want one dimmer for all the lights. They are too bright but I don't want to buy less brights bulbs in case I want the brightness at times

I turned the breaker off and all the lights go out so wouldn't that tell me it's on the same circuit?

If the wires in the box are that hard to figure out, then there is probably another circuit in the box. It is a common practice.

You need to take the bulb out of the recess can and then take the trim off. On the inside of the trim it will tell you the maximum wattage for different kinds of bulbs. Take a picture of the bulb so I can tell you what kind it is. It sounds like you have more than one problem that can be dangerous here. It would take an electrician no time at all to explain to you what all is going on in your house while putting in dimmers. If you move your bed to between the windows, you may understand why they are on separate switches. You have two recess cans with soft white light so it doesn't glare in the other persons face while sleeping. And two with bright lights that are AWAY from the intended bed location for getting dressed in the morning in the middle of the dark, cold winter. Also I need to know the wattage of the heat lamps.

@ Fred S If they are on the same circuit, you can put a dimmer to control all 4 lights.If they are not on the same circuit,you cancel one circuit and put all lights on the same circuit. Any qualified electrician can do this in less than 15 minutes.
From the Lutron website:
"Selecting the right Lutron dimmer wattage:
Dimmers are rated for maximum wattage:

Incandescent dimmer wattages are usually max 600W or 1000W.

@ Fred S If you don't know what you're talking about, you should stop commenting.

Hooboy!
Fred is right, why take a chance on this stuff? Call an electrician.
As well, depending what KIND of recessed lights you have, you can't just put any old dimmer on there. If they are MR16's, they require a magnetic low voltage dimmer, for example, not a "standard" dimmer.
Do you want to be able to turn these on/off at a second location? Then you'd need a 3-pole dimmer...
These are just two simple examples of why this question is far more complicated than a yes/no answer. I never assume anything when it comes to electrical, I rely on the experts in the field.

The mere fact that you're on this forum asking this question tells me you need to hire a qualified electrician. Yes, you might be able to figure it out by reading some books or watching some Youtube videos, but when was the last time you watched the nightly news about some house on fire that was attributed to "faulty wiring"........wood studs, and much of today's construction materials, and over heated wiring is not a good thing to have...................are you willing to bet your house, your possessions........even your family's lives on a "I think it's right" notion.....? Hire a qualified electrician and think of it as doing your part in fueling the economy.

There was probably a reason that the electrician ran this on multiple circuits ... BUT WAIT, there is more :)

I would recommend going completely outside the box on this one, if you really want to gang them together and have them operate ... have you thought about an inexpensive automation switch? You could replace each switch with a dimmer then add a programmable keypad next to them to program scenes.

We use a lot of Control4 systems and are now in talks with moving to an all low voltage lighting option, but in the meantime there are plenty of websites that sell "smart" switches that could even be controlled by your smart phone!

I've already assessed the situation and will be calling an electrition

Red Bud
Can you give me more info about the automation switches?

Control4 is a system that you need to purchase through a licensed dealer, I am not sure where you are located but I am sure that there are some dealers in your area.

You could also look at the options available at smarthome.com ... If you are only doing the one room, I don't think that I would recommend using Control4, but if you want to integrate audio, video, lighting, and shade control ... control4 becomes a very competitive option. Good luck!