How to choose a rope
A dynamic rope is what absorbs a fall. The right choice depends on where you climb, how often and what kind of routes.
Single, half or twin
A single rope is used on its own and is the standard for the gym and sport climbing. Its end is marked with a 1 in a circle.
Half ropes are used as a pair, each clipped into separate protection. They reduce drag on wandering routes and allow full-length abseils. They are marked ½.
Twin ropes are used as a pair and always clipped together into the same carabiner. They are marked ∞.
Diameter
Thicker ropes (about 10 mm and up) are more durable and better for heavy use, the gym and working routes. Thinner ropes are lighter for hard routes and long approaches, but wear faster. Check that your belay device is rated for the diameter you choose.
Length
The rope must be at least twice as long as the longest route you lower from. In many areas 60 m is enough for sport climbing, and 70 or 80 m is chosen for longer routes. Check the guidebooks for the crags you climb at.
Dry treatment
Dry-treated ropes absorb less water and dirt. For the gym and dry rock it is not essential, for snow, ice and wet days it is.
Certification and care
Dynamic ropes are tested to EN 892 and UIAA 101. Use a rope bag, do not step on it and keep it away from chemicals and sharp edges. For when to retire it, read the PPE inspection guide.