Climbing Ropes: Which Rope Is Right for You?

The rope you should buy depends entirely on the kind of climbing you plan to do. Every climbing rope worth considering is tested and certified by the UIAA, and each comes with similar information. Let's decode that information first, using a 9.9mm single rope (the Trango Lotus 9.9) as an example, then look at what to buy for different types of climbing.

Specs marked with an asterisk come from UIAA lab tests. Use them to compare ropes to each other, not to predict exactly how a rope will behave at the crag.

How to read climbing rope specs

Rope type (example: single)

A single rope can be used on its own to climb on rock. Half and twin ropes are designed to be used in pairs, although halves are sometimes used alone on snow. The UIAA certifies each rope as a single, half and/or twin using a different test for each. If you're not sure what you need, stick with a single.

Length (example: 70 meters)

Most modern ropes are 60m or 70m. A 70m rope gives peace of mind on long routes and lets you cut off worn ends later (most wear happens in the last few meters). A 60m rope saves weight and money. Shorter ropes are for the gym.

Diameter (example: 9.9mm)

Single ropes range from about 8.9mm to 11mm, but most climbers use ropes in the 9.2-10.2mm range. A larger diameter generally means a thicker sheath, more durability and more weight. Belay devices work better with some diameters than others, so check the device manufacturer's recommended range.

Static elongation* (example: 9.4%)

How much the rope stretches when a standard weight (80 kg, about 176 lb, for single ropes) hangs from it.

Dynamic elongation* (example: 34%)

How much the rope stretches during the UIAA drop test, which simulates a near worst-case fall.

Impact force* (example: 7.9 kN)

The peak force generated during the UIAA drop test. One kilonewton is roughly 225 pounds of force. Lower numbers mean a softer catch.

UIAA falls* (example: 7)

The number of brutally harsh test drops the rope survives at short intervals before breaking. It is NOT the number of falls your rope can take. A well-maintained rope can catch hundreds of normal falls. Use this number only to loosely compare durability between ropes.

Dry treatment (example: sheath dry)

Dry treatments keep fibers from absorbing water, which significantly weakens a rope, and help repel dirt and grit that wear it down. Untreated ropes are more affordable and work fine if kept clean. A sheath treatment helps anyone climbing outside; a core treatment is essential if your rope may get wet, such as on long routes in stormy country or on glaciers.

Midpoint (example: center mark)

Most ropes have a dyed center mark or a bi-pattern weave (each half looks different). These help you avoid lowering a climber off the end and center the rope for rappels. Do NOT mark your rope's center with tape: the adhesive breaks down and the tape can slide. This has been linked to at least one fatality.

Which climbing rope should you buy?

Most climbers buy their first rope because they're starting to climb outside, or because they top-rope in the gym and want to start leading. Here's what we recommend for each, plus options for alpine climbing.

1. Your first outdoor rope

As a new outdoor climber, you'll mostly be top-roping, and when you start leading you probably won't be pushing hard grades right away. Choose a 60m or 70m rope at least 9.5mm thick; 9.8-10.2mm is ideal, though belay device compatibility becomes an issue at larger diameters. A sheath dry treatment pays for itself in longevity. A center mark is usually easier for the belayer to notice than a bi-pattern, and it costs less. UIAA specs will be similar among ropes in this category, and you likely won't feel the difference in the field.

2. A gym rope

Gym-specific ropes typically come in shorter lengths with 9.8-10mm diameters, which is perfect. No dry treatment is needed since a gym rope shouldn't be used outside. To save money, team up with a friend and split a 70m rope into two gym ropes. Most gyms are fine with a 35m rope, but check with your gym if its walls are especially tall. Ask our staff for help cutting and finishing your rope.

3. Alpine and long multipitch ropes

For mountaineering or long alpine climbs, consider a lighter single or a pair of half ropes. Two ropes make long retreats easier, add safety where rockfall or crampon punctures are a concern, and can save weight. Many mountaineers carry a single 30m half rope to protect against crevasse falls or to belay less experienced partners up short technical steps. Twin ropes are clipped together into every piece of protection and are very dynamic; they're popular on long bolted routes in Europe but uncommon in the U.S. Our author's choice for long rock routes is a 70m, 9.2mm fully dry-treated single. Weight-conscious climbers may go thinner, at the cost of durability.

What about static rope?

Static line is for hauling, ascending fixed lines and industrial work. Unless you're certain you need it, you don't. Never use static rope for lead climbing or top-roping: it doesn't stretch to absorb the force of a fall.

Shop climbing rope accessories

Climbing ropes, harnesses and belay devices are available in-store at our Grand Avenue store in Portland's Central Eastside. Swing by to check out our selection, get advice, or just say hi.