Outdoors & Fitness · Head-to-head
Petzl GRIGRI vs Black Diamond ATC-Guide
Which should you buy? Our verdict on both, pulled from our full The Best Belay Devices: 4 Compared (and One to Skip) comparison.
The GRIGRI is the most forgiving device here for the single-rope lead and top-rope belaying that most people do most of the time, and Petzl is unusually specific about which rope diameters it works best on. The ATC-Guide costs a fraction as much, weighs less than half as much, handles half and twin ropes, and its guide mode can bring up two seconds at once off an anchor, which the one-person GRIGRI cannot.

Petzl GRIGRI
Buy itThe cam-assisted device that most gyms and sport crags are built around, with the clearest published guidance on which ropes it likes.
- Certified to EN 15151-1 type 6, the part of the standard for braking devices with manually assisted locking, which none of the other three here carry.
- Petzl publishes a certified range of 8.5 to 11 mm plus a narrower optimal band of 8.9 to 10.5 mm, so you can check your rope against a real number rather than guessing.
- The handle gives smooth, controllable lowering once you have been taught the technique, which is a genuine advantage over the passive devices.
- At 175 g it is the heaviest of the four by a wide margin, and it is the one you notice on a harness all day.
- No guide mode: Petzl's notice covers lead and top-rope belaying, lowering and single-strand rappel, and belaying a second is covered only in a separate Petzl tech tip, one climber at a time.
- Petzl warns that pinning the cam with your thumb while feeding slack can negate the blocking action, which is exactly the habit beginners pick up.

Black Diamond ATC-Guide
Buy itThe cheap, light, do-everything tube with a guide mode, and the device that covers the widest range of ropes here.
- 8.1 to 11 mm of published rope compatibility in 80 g of aluminum, the widest range in this comparison.
- Guide mode belays one or two seconds off an anchor; the CLICK UP+ cannot belay from the anchor at all, and the GRIGRI handles one person at a time.
- Two friction settings, which is why Black Diamond certifies it as EN 15151-2 Type 4, a manual braking device with a function to adjust friction.
- No assisted braking on a lead belay at all: the holding power is entirely your brake hand and the rope's angle.
- Black Diamond's own instructions warn that if you belay two seconds in guide mode and one hangs on the rope, the locking function may not work on the other second's rope.
- Lowering a second out of guide mode is an awkward, learned procedure and a common place for people to get stuck.
Side by side
The 8 criteria below are the ones our full comparison judged every product on, narrowed to these two.
| Petzl GRIGRI Our pick | Black Diamond ATC-Guide | |
|---|---|---|
| Our verdict | Buy | Buy |
| Best for | Sport climbers and gym regulars belaying a leader on one rope who want the most margin for error on the catch. | Anyone who climbs multipitch, rappels, or wants one device that handles single, half and twin ropes. |
| Price tier | $$$ · premium | $ · budget |
| Device family | Cam-assisted braking | Tube with guide mode |
| Certification as published | EN 15151-1 type 6, UIAA | EN 15151-2 Type 4 |
| Certified rope diameter | 8.5 to 11 mm single | 8.1 to 11 mm |
| Maker's optimal range | 8.9 to 10.5 mm | Not published as a narrower band |
| Weight | 175 g | 80 g |
| Belays a second from an anchor | One second, in a Petzl tech tip rather than the notice | Yes, one or two seconds |
| Main materials | Aluminum, stainless steel, nylon | 100% aluminum |
| Belay carabiner requirement | Petzl locking or directional carabiners, otherwise run a compatibility test | Carabiners meeting EN 12275 Type H |
Which one is right for you?
Pick the Petzl GRIGRI if
sport climbers and gym regulars belaying a leader on one rope who want the most margin for error on the catch.
Know before buying: at 175 g it is the heaviest of the four by a wide margin, and it is the one you notice on a harness all day.
Pick the Black Diamond ATC-Guide if
anyone who climbs multipitch, rappels, or wants one device that handles single, half and twin ropes.
Know before buying: no assisted braking on a lead belay at all: the holding power is entirely your brake hand and the rope's angle.
The bottom line
Our overall pick is the Petzl GRIGRI - The cam-assisted device that most gyms and sport crags are built around, with the clearest published guidance on which ropes it likes. Choose the Black Diamond ATC-Guide instead if anyone who climbs multipitch, rappels, or wants one device that handles single, half and twin ropes.
Want the full picture, including the other options we compared and the popular one we'd skip? Read the complete The Best Belay Devices: 4 Compared (and One to Skip).