Most climbing gyms in North America grade their boulders on the V-scale. Every climb has a strip of tape at its start with a grade, and the higher the number, the harder the climb. Many gyms also use tape colours that group a few grades together.
- V0 to V1: big holds close together. Most beginners climb one in their first session.
- V2 to V3: smaller holds, and moves where good footwork matters.
- V4 to V5: steeper walls and harder moves in a row, usually after months of regular climbing.
- V6 and up: climbs that strong, experienced climbers work on over several visits.
Grades are a guide, not a rule. A climb can feel easier or harder depending on your height, reach and style, and every gym grades a little differently. Start a grade or two below what you think you can do, try climbs of the same grade on different walls, and move up when most of them feel steady.