Depending on what you want to climb the needed items can be quite different. There are also supplies that you might want to help you climb better but are not required. Technically you can climb with absolutely nothing which is illustrated by the free climbers who like to climb without any ropes or safety equipment. Some of them have even taken it to the next level and climbed up mountains wearing only their skin. I wouldn’t recommend taking after them for several reasons. The main one is that the equipment is designed simply to keep you safe in the case of a fall and climbing without it can be deadly on higher climbs. The second reason is that I imagine it wouldn’t be very comfortable or warm trying to climb at high altitude with nothing on.
1. Climbing harness.
The harness of course is essential both when climbing indoor and outdoor. It is the thing that’s keeping you from falling to the ground. It’s made up of two loops that go around each of your legs and one around your waist. The harness a simple design but if you’re using it for the first time make sure you ask someone, who knows what they’re doing, to show you how to tie in and secure the harness. You can rent harnesses at gyms but they aren’t as comfortable as bought ones and for outdoor climbing you generally have to have your own.
2. Shoes.
I’m not talking about normal shoes, to climb you almost always need climbing shoes. They aren’t needed for your safety but they allow you to use your feet much more effectively. If you’re trying anything close to difficult you really do need them. They are lace up shoes that have thin rubber soles, toes, and heels. They aren’t very comfortable because they squeeze your feet to make them better for climbing but are very useful.
3. ACT/belay device with carbineer.
This is needed for when you belay someone at any time. The rope runs through it and allows you to feed rope out for the climber, bring it in, or “brake” the rope when the climber falls. You need to be instructed on the use of a belay device before you use it so that you don’t let your partner fall.
4. Chalk bag.
I personally don’t use this except for longer climbs because my palms don’t sweat very much but chalk is used to dry out your hands and give you a better grip on the rock.
5. Rope.
Obviously you need this to secure yourself to the face. Without it you would be free climbing and before you do that make sure you’re ready.
6. Gear according to surroundings.
There is a lot of such gear that you might need depending on where you climb. You might need to place your own gear in the rock or rope could already be up and ready to be climbed. If you’re ice climbing then you might need ice axes and crampons. The different scenarios are extensive and I hope you can think for yourself about what you need.
7. Anything I forgot.
I’m sure I forgot some things so if you think of something that makes sense but isn’t down here make sure you bring it. Better to have it and carry it around then get to the climb and find out that you forgot your helmet for a loose face or sunscreen in the direct sun.