In North America both sport and trad rock climbs are graded using the YDS (Yosemite Decimal System). This system starts at 5.0 (like climbing a steep ladder) and progresses in difficulty up to 5.15 (an overhanging cliff). The grade of a rock route is usually based on the crux, the most difficult move. The first climber to complete a route assigns a grade, which can change as more people make the ascent and come to a consensus.

Grades are subjective. Standards vary among climbing areas. Routes may feel substantially harder than their grade indicates depending on the weather, the length of the route, the type of rock, the whims of the first ascensionist, any number of factors.

Use this chart as a rough guide to compare climbing and bouldering grades in other parts of the world.