A bouldering grade is a number — sometimes plus a letter — that estimates how hard a boulder problem is. Grades let climbers communicate difficulty, plan progression, and track improvement. Two grading systems dominate worldwide: the V scale (V0 to V17, used in the US and most of the world) and the Font scale (4 to 9A, used in France and parts of continental Europe).
Bouldering grades are more subjective than weight or distance — they reflect community consensus, not objective measurement. A V5 at one gym may feel like a V4 or V6 at another. Outdoor grades tend to feel harder than indoor grades because conditions, footwear, and the pressure of climbing on natural rock all affect performance. New climbers sometimes obsess over grades; experienced climbers care more about the moves and movement quality than the number.
Other grading systems exist for context: the YDS (Yosemite Decimal System) for roped climbing in the US (5.5 to 5.15d), the British E-grade for trad, and the UIAA scale used in some German-speaking countries. Bouldering specifically uses V or Font almost exclusively. Most beginners progress from V0–V1 in their first months to V3–V4 within a year of regular climbing, then slow as the grades get harder.