The best bike lock balances security and ease of use
The National Bike Registry estimates that 1.5 million bicycles are stolen each year, and a vast majority of these thefts aren't reported to authorities. Priceonomics.com notes that most thieves probably don't make a whole lot by reselling selling stolen bikes, but the risk of getting caught is low (and the punishment, if anything, is negligible). Because of that, bike theft continues to flourish -- to the tune of roughly $350 million a year, according to the FBI.
Experts say you shouldn't think twice about investing at least 10 percent of your bike's value in a good lock or even multiple locks. There are several popular styles available, including chain locks, cable locks and U-locks. The best bike locks perform well in security tests but will be light enough to transport, or come with an easy-to-use mounting bracket. They should hold up to daily abuse, not damage your bike, and include a strong manufacturer's anti-theft protection plan. These plans can be time-consuming to enroll in and require some paperwork, but may be well worth it in the long run.
Bikes of all sizes are vulnerable to getting snapped up. If your kiddo needs a new bike, check out our separate report on kids bikes for our top recommendations, and be sure to protect it as well.
Heavy chain locks are best for keeping bikes safe
Chain locks have tough steel links that are typically connected to a small disc lock that requires a key to open. They can be quite heavy, with heavier, thicker chains generally offering better security. Because chain locks can be quite long -- some are 6 feet or more -- they're especially good for keeping multiple bikes safe or securing bikes to larger anchors such as lampposts or benches. But because of their weight, they're probably best suited for keeping a bike safe near home or another place where the lock won't often have to be moved.
Cable locks are convenient, but not as secure
There are numerous cable locks on the market, but you won't find many experts who recommend them if you really want to protect your bike from thieves. Cable locks use steel cables attached to a combination lock, key lock or padlock; you simply thread the cable around your bike frame and through both wheels (and around the seat, if you have enough cable). Unfortunately, they can be broken in seconds using a simple tool such as a bolt cutter. Still, they can be a decent secondary option when used in combination with a tougher chain or U-lock. Many riders also love cable locks because they're lightweight and easy to carry, saying they're convenient for warding off an opportunistic thief or for use in very low-crime areas.
U-locks offer a mix of portability, protection
In general, experts say U-locks provide the best protection against bike theft. U-locks have a thick steel shackle attached to a crossbar with a keyed lock. Sized properly, they don't leave much space for someone to insert a crowbar or other tool between the bike and anchor, helping minimize leverage that can be used in a theft. They are generally lighter and more portable than chain locks, and their smaller size makes them easy to put in a backpack or mount on your bike frame for travel. However, U-locks aren't large enough to protect your whole bike. Urban bicyclists often use a U-lock to secure the frame and back wheel of their bike to an anchor like a lamppost or bike rack, and use a secondary U-lock, chain lock or cable lock to secure the front wheel.
How we chose the best bike locks
There are several expert tests that pit a range of tools (some even wielded by real bike thieves) against all kinds of bike locks to see which hold up best. Some of the best were conducted by TheSweethome.com, OutdoorGearLab.com, and Gizmodo.com. There were also helpful, in-depth reviews and roundups from sites such as GearPatrol.com, HiConsumption.com and Bike Radar.com. We cross-referenced these test results and recommendations with owners' real-world experiences with bike locks as reported at sites such as Amazon.com, REI.com and PerformanceBike.com. The result is our recommendations for bike locks with the best combination of security, ease of use and durability.
The best chain and cable bike locks
Bike chain locks generally don't fend off attacks as well as U-locks, and they're heavier and bulkier to carry. Still, they look imposing and tough, and experts say they're a good option for securing several bikes together. Cable locks are much lighter and more portable, but don't offer the protection of beefier chains. Still many bike owners love cables because they're easy to toss in a backpack and they can ward off opportunistic thieves during quick stops.
If you don't mind paying for a top-notch chain lock -- and you won't need to tote it around -- reviewers say the Kryptonite New York Fahgettaboudit Chain (Est. $115) is your best bet. BikeRadar.com's Warren Rossiter calls it "strength-wise … simply one of the best." Even with power tools, it took him nearly two minutes to cut through just one of the six-sided, 14mm manganese steel chain links. In similar tests by Slate.com, the chain "shook it off and continued to work like new" when attacked with a variety of tools.
Make no mistake: the Fahgettaboudit is massive and heavy. The lock is available in 3.25- and 5-foot lengths. The shorter chain weighs 10.8 pounds, while the longer chain weighs a whopping 15.25 pounds. Reviewers say it's ideal for securing a bike at a permanent location like your home where you won't often need to move the lock, or for securing multiple bikes together. But they're unanimous on this point: It's not a lightweight lock you'll want to ride with.
The Fahgettaboudit comes with a disc lock that has a 15mm steel shackle and a hardened double deadbolt. It includes a dust cover to keep the lock cylinder clear of dust and debris. A nylon cover prevents the chain from scratching or nicking bikes. Three stainless steel keys are included, and one has an LED light. However, reviewers warn that this light is flimsy and breaks easily. The lock comes with one year of theft protection up to $3,750, which is generous; however, you'll need to present proof of the broken lock to be eligible.
If the price or weight of the Fahgettaboudit is too hefty for you, the OnGuard Mastiff (Est. $65) also offers beefy protection at a more reasonable price point, reviewers say. One of Bicycling.com's "top performers," the lock resisted bolt cutters and a hacksaw, and even outlasted an angle grinder. The 10mm square links are made of reinforced titanium.
The Mastiff comes in 3.5- and 6-foot lengths that weigh about 8 and 11 pounds, respectively. Though that makes it lighter than the Fahgettaboudit, the Mastiff is still more ideal for deterring thieves in high-crime locations where it won't often have to be moved, reviewers say. The longer lock is particularly good for securing multiple bikes.
The Mastiff comes with an integrated double-bolt lock that has a rubber cover to protect both the lock cylinder from debris and the bike from scratches. A water- and heat-resistant nylon chain cover also helps minimize paint damage. Five laser-cut keys are included; one has a micro light. The lock comes with a $2,000 one-year theft protection plan that isn't available to customers in the state of New York. Like Kryptonite, OnGuard requires you to send in the broken lock to receive coverage.
If you're willing to sacrifice some security in the name of portability, the wearable Hiplok Lite (Est. $60) chain lock could be the answer. Its 6mm hardened steel chain isn't as hefty as the chains on the Fahgettaboudit or the Mastiff, and Bike Radar's Andrew Dodd says it's most ideal for deterring opportunists -- but likely not the most determined bike thieves. Still, it resisted bolt cutters in his tests, and many reviewers say it's still tough enough for all but high-crime areas.
Designed to be worn like a belt, Hiplok Lite adjusts to fit waists from 28 to 44 inches. It also weighs only 2.2 pounds -- a far cry from the much heavier Fahgettaboudit and Mastiff. If you're less concerned with weight and want a portable, wearable lock that might withstand more than opportunists, the 5.3-pound Hiplok Gold (Est. $110) has a 10mm hardened steel chain. Some reviewers grouse that Hiplok Lite, which is about 2 feet long, is a bit too short for anyone who may need to lock a bike to a lamppost or something other than a bike rack or slender pole.
The disc lock on Hiplok Lite has a 10mm hardened steel shackle and a molded nylon case that comes with three keys. The chain has a protective black sleeve to protect bikes from paint damage and make the lock more comfortable to wear. One version, Hiplok Lite Superbright (Est. $60) has a reflective white sleeve for increased visibility.
While experts caution that you shouldn't make a cable lock your bike's sole means of protection, they do recommend them in combination with heftier locks. Reviewers say the 12mm braided steel OnGuard Akita Resettable Combo Cable Lock (Est. $25) is one easy-to-use cable option that has a lot of plusses. Remember, however, that top-notch security isn't one of them: in tests conducted by OutdoorGearLab.com, the cable fell victim to "a variety of inexpensive household items," such as garden shears. Most owners caution that this cable lock is best for low-crime areas or quick stops.
Weighing in at just 1.2 pounds, the Akita is lightweight, but Outdoor Gear Lab's Rylee Sweeney says it's not as easy to transport as a coiled cable lock that's designed to wrap up into a smaller, neater package. Still, wrapping the 6-foot cable "isn't too much of a hassle," and it's easy to secure with the included Velcro strap, Sweeney says. The cable is also easier to thread through a bike's frame and wheel than a coiled version, she notes.
The Akita comes with a steel ball combination lock that wasn't easily picked in expert tests, and owners say it's easy to set. The rubber-coated lock head helps prevent paint damage to bikes. If you prefer to forgo the combination lock, the OnGuard Akita Key Cable Lock (Est. $18) comes with an integrated double-bolted key lock and is available in more lengths, ranging from 3.2 to 9.7 feet.
Elsewhere in this report:
Best U-Locks | Buying Guide | Our Sources