In five minutes time, you can order a coffee, check your email, politely glance at the other café-goers, receive said coffee, and return to where you left your unlocked bike, which was stolen four minutes ago. Shouldn’t have asked for an extra shot, but hindsight is 20/20 and now your prized bicycle is listed on a neighboring city’s Craigslist for pennies of what you paid. The FBI reported 131,777 bike thefts in 2018, although the real number is likely higher because many property crimes go unreported. An Oregonian analysis of 13,000 Portland bicycle thefts found that only 2 percent of reports ended in arrests, which means your bike is probably gone for good.

Best U-Lock Kryptonite New York STD amazon.com $114.95 SHOP NOW Designed for ultimate urban protection, backed by $4,000 in theft protection. Wearable Hiplok Spin amazon.com $49.99 SHOP NOW This lightweight chain lock disappears on your waist. Best Chain OnGuard Mastiff amazon.com $124.95 $79.95 (36% off) SHOP NOW This tough 3.5-foot chain is high-value security. Bike-Mounted Lobster Lock amazon.com $74.99 SHOP NOW This folding lock attaches to your bottle bosses. Lightweight Ottolock Cinch competitivecyclist.com $55.00 SHOP NOW Small enough to be portable, yet surprisingly strong.

The good news is bike thieves are criminals of opportunity, so you can decrease your risk by locking up more intelligently than the next cyclist. Let’s run through the pros and cons of each genre to help you pick the best lock for your situation.

Four Types of Locks

A thief with the right tools can defeat any bike lock in five minutes, but that doesn’t mean all locks are created equal: The crook will raise hell cutting through a hardened-steel U-lock or chain with an angle grinder, so he or she is more likely to go after a cheaper, lightweight cable lock with a set of bolt cutters. To decide how much security you need, consider your location and duration of lockup.

All-day lockups on college campuses and in major metro areas where thefts are common require more security, says Kryptonite brand manager Daryl Slater, and anything left out overnight necessitates paranoia-level countermeasures (using multiple locks that can’t be defeated by the same bolt cutters is a good start). Here’s how the basic lock types differ, in order of most to least secure.

Can My Lock Be Picked?



Just like all bike locks are eventually susceptible to cutting attacks, all bike locks can also be picked. But most modern locks can’t be defeated by amateurs, says competitive lock picker Schuyler Towne. Disc detainer locks, which use a series of rotating discs, are considered the most difficult to pick. Slider locks, like those from OnGuard, have keys with laser-cut slots and flat sides and can provide high security. “The more cuts on the key, the more secure it is,” Towne says of slider locks.

Bike locks may have different locking mechanisms, but most use a similar basic construction to the pin tumbler lock (above). The key goes into a plug that sits within a cylinder, and a series of pins, wafers, discs, or sliders prevent the plug from turning without a key. Wikimedia Commons In a pin tumbler lock, a series of spring-loaded pins prevent the plug from turning. Inserting a key, or picking the lock, lifts the tumblers to clear the shear line—where the plug meets the cylinder—and opens the lock. Wikimedia Commons

Pin-tumbler locks are a classic design that can sometimes be foiled by brute force attacks, although others require more skill. And wafer locks are considered the least secure—more vulnerable to entry-level picking—but individual wafer locks may prove more secure than others. Find a detailed description of each type of locking mechanism at the bottom of this guide.

Using Your Lock

Once you’ve bought a lock, you have to put it to work. “Make sure you lock according to value,” Slater says. “The frame (being most expensive), the rear wheel, then the front wheel.” Unlocked frames and wheels will likely be stolen eventually, so your best bet is locking both wheels to the frame with a chain or cable lock (or another U-lock, in high-risk areas). Aim for well-lit places and never leave a lock against the ground, as thieves might get the necessary leverage to pry it open. Make sure your bike can’t be lifted up and over a poll or tree. Slater says he’s encountered victims whose bikes were locked to street signs, over which a bike can easily be hoisted, or small trees, which were promptly cut down. As a general rule, the thing you’re locking to should be stronger than your lock. Lastly, take down your bike’s serial number (under the bottom bracket) and register it with your local police department in case the worst happens.

How We Chose

Every lock here has been thoroughly evaluated and vetted by our team of test editors. We research the market, survey user reviews, speak with product managers and engineers, and use our own experience with these locks to determine the best options. We’ve used these locks, weighed them, and evaluated their mechanisms. We’ve cut a few in individual tests, and we’ll update this guide with full destructive testing as soon as we can return to our office. For now, we’ve researched testing and picking conducted by outlets like Wirecutter and Bike Radar and experts like LockPickingLawyer to identify the best locks in each category.

We ruined the blade of our hacksaw before we made a dent in the Hiplok DX. Ultimately, we cut the shackle with a five-inch DeWalt cordless angle grinder in about 30 seconds. In a different test, a Kryptonite New York lock withstood about 40 seconds of cutting. (Both locks require two cuts to open the shackle.) Trevor Raab

Now that you’re lock literate, check out these 17 options for securing your bike and shackling down some peace of mind.

Kryptonite New York

Weight: 4 lb. | Frame mount? Yes | Locking mechanism: Disc detainer



Kryptonite New York Lock $114.95 SHOP NOW amazon.com High security

Relatively lightweight Flimsy mounting bracket

All you need to know about the Kryptonite New-U New York Lock is in the fine print: The company will replace your bike (up to $4,000) if it’s stolen because the lock was compromised in Manhattan, where thousands of bikes are stolen each year. The u-lock has a 16mm hardened steel shackle and uses a pass-through crossbar design to prevent twisting attacks, forcing thieves to cut the shackle twice to compromise the lock. From personal experience, the four-pound lock works great as a mallet, too. The included mounting bracket uses a nylon strap to affix to the frame rather than going through the bottle bosses, a design that increases available mounting positions. However, the design relies on friction to keep the lock in place, so user reviews are mixed on whether it works long-term. One crafty Amazon reviewer used his or her own hardware to screw the mount to the bottle bosses, which might prove sturdier than the friction mount.

OnGuard Brute STD 8001

Weight: 3.8 lb. | Frame mount? Yes | Locking mechanism: Slider

Brute STD 8001 OnGuard amazon.com $74.95 $59.32 (21% off) SHOP NOW Secure

Wide shackle for more lock-up options Flimsy mounting bracket

The OnGuard Brute STD presents a square-shaped shackle that widens the diameter of available lock-up poles. The shackle is 16.8mm of hardened steel, and the key hole closes automatically to keep the elements out. The lock comes with a mounting bracket, and at $5,001, OnGuard’s anti-theft protection is exactly $1 higher than Kryptonite’s. And like Kryptonite’s U-locks, the Brute STD’s included mounting bracket isn’t great—numerous reviewers report it breaking after a few months.

Hiplok DX

Weight: 2.4 lb. | Frame mount? No | Locking mechanism: Pin tumbler

Hiplok DX Lock $89.99 SHOP NOW backcountry.com Lightweight

Clips to waistband

Urban cyclists have for years been stuffing mini U-locks into back pockets and beneath belts, which works fine but isn’t too comfortable. So Hiplok reimagined the U-lock with a crucial addition: a clip. With it, the lock slides onto your waistband and isn’t annoying to ride with, so long as you have a tight enough waistband. The rest of the lock is formidable, with a 14mm shackle that locks on both sides of the crossbar. In an individual test, the shackle defeated the blade on our hacksaw rather quickly, but fell victim to a five-inch cordless angle grinder in about 30 seconds—an average time for cutting a hardened steel shackle, and two cuts are needed to defeat this lock.

RockyMounts Warrant

Weight: 2.4 lb. | Frame mount? No | Locking mechanism: Disc detainer

RockyMounts Warrant $59.86 SHOP NOW amazon.com Compact

Cheap Small shackle limits lock-up options

RockyMounts’s Warrant U-lock packs a lot of security into a small package, with a 14mm hardened steel shackle and a disc detainer mechanism. The outside is coated in silicone to prevent the shackle and crossbar from scratching your bike, and dimples on the shackle keep it from being twisted if a single cut is made.

Altor SAF

Weight: 13.8 lb. | Frame mount? No | Locking mechanism: Disc detainer

Altor SAF Lock $299.00 SHOP NOW amazon.com Extremely difficult to cut Expensive

Heavy

When it debuted last year, the Altor SAF Lock set out to be the world’s first angle grinder-proof lock. For practical purposes, it succeeded: We burned through six batteries and four grinding discs before we finally managed to cut the lock . Its defense is its thickness: A five-inch angle grinder, the most popular variant, doesn’t have enough cutting depth to go straight through, so thieves are left to hack at an aluminum shell and hardened steel core (and make a few return trips to Home Depot before the job is done). Downsides? It’s 13.8 pounds, so definitely not portable on a bike, and it’s likely that the pole to which you’ve locked up is much easier to cut than the lock itself. That said, you’re less likely to be stolen from if your lock is bigger than the next bike’s, so the SAF Lock is tough to beat as a stationary security solution.

Master Lock Bicycle U-Lock

Weight: 1.9 lb. | Frame mount? Yes | Locking mechanism: Wafer

Bicycle U-Lock Master Lock amazon.com $24.89 SHOP NOW Cheap

Lightweight Crossbar doesn’t prevent thieves from twisting the shackle off after a single cut

Master Lock’s Bicycle U-Lock is among the least secure U-locks we’ve encountered, but for $16, it’s still significantly more secure than a comparably priced cable lock or zip-tie style lock. The hardened steel shackle stood up to metal shears and a 2-foot set of bolt cutters, and the crossbar survived attacks from a hammer and a crowbar. We’d expect the shackle to fail pretty quickly from a cutting attack—stay tuned for destructive testing in the next update—and thieves need only make one cut, as the crossbar doesn’t prevent the shackle from twisting. Still, for light to medium security, it’s tough to beat this $16 U-lock.

Abus Bordo Granit X-Plus 6500

Weight: 3.8 lb. | Frame mount? Yes | Locking mechanism: Disc detainer

Courtesy of Abus ABUS Bordo Granit X Plus 6500 $179.99 $85.25 (53% off) SHOP NOW amazon.com Compact

Quality bike mount Pricey

The Bordo Granit X-Plus 6500 is another folding alternative to unwieldy U-locks and chains, yet at approximately 3.5 pounds, it’s no lightweight. The 5.5mm links are designed to withstand cutting attacks, although the connecting pins appear to be unhardened, so they might not survive attacks from long bolt cutters or nut splitters . The carrying case has loops to secure the lock to your frame for easy schlepping and swapping between bikes. The bottle bosses and lock will add a bit of heft to your bike, but we didn’t feel inconvenienced by it.

Altor Apex

Weight: 2.4 lb. | Frame mount? Yes | Locking mechanism: Disc detainer

Altor Apex $148.00 $98.00 (34% off) SHOP NOW amazon.com Lightweight

Elegant design Pricey

Altor’s Apex folding lock is an elegant device with a premium feel to match its price. At 2.4 pounds, it’s among the lighter folding locks. Its bottle mount held up; in testing, the Apex stayed put and didn’t rattle as we pedaled. Unfolded, it’s just big enough to secure your frame and front or rear wheel. Its hardened steel construction should be formidable against hand tools; reviewers at Wirecutter were able to drill through the hinges of the previous version, the 560G, but the Apex has hardened steel joint caps to protect the rivets from drilling attacks. (A previous version of this review incorrectly stated that Wirecutter had drilled through the Apex, not the 560G.)

Lobster Lock

Weight: 2.7 lb. | Frame mount? Yes | Locking mechanism: Wafer



Lobster Lock Lobster Lock amazon.com $74.99 SHOP NOW Stays on bike at all times Wafer lock is less secure

The Lobster Lock is a folding lock with a neat trick: It’s always attached to your bike. The device screws into your bottle bosses and stays there, although you can still mount a bottle cage above the lock. To lock up, you unfold the arms on each side of the lock and wrap them around the frame and front wheel, connecting them with a locking mechanism at the ends of the arms. We haven’t done destructive testing (yet) to gauge the strength of the arms and hinges, but the wafer locking mechanism is a possible weak point for entry by picking.

RockyMounts Hendrix

Weight: 1.6 lb. | Frame mount? Yes | Locking mechanism: Disc detainer

Courtesy of RockyMounts RockyMounts Hendrix $69.95 $55.96 (20% off) SHOP NOW amazon.com Lightweight 27-inch folding circumference limits lock-up options

The Hendrix is one of the smallest non-cable locks you’ll find, and RockyMounts includes a holder that mounts on your frame’s bottle bosses for easy portaging. The 5mm steel links present a challenge for cutting tools, and hardened pins aim to resist power drills, although we wouldn’t consider this a high-security lock (RockyMounts rates it a 7 out of 10 on its own security scale). But if you’re looking for a medium-security lock to fit in a jersey pocket, the Hendrix might be the best pick.

Hiplok Gold

Weight: 5.3 lb. | Frame mount? No | Locking mechanism: Pin tumbler

Courtesy of Hiplok Hiplok Gold $129.99 SHOP NOW amazon.com Wearable design for convenient carrying Too big for waist sizes smaller than 30 inches

The Hiplok Gold is a chain lock designed to be worn. Rather than locking to your waist—a potentially dangerous move if you crash—the chain has a patented nylon clip and hook-and-loop waist adjuster to close around your torso. It also features a burly 10mm-thick hardened steel chain and a 12mm hardened steel shackle that’s encased in a nylon shell. The sleeve surrounding the chain is removable and washable, and its reflective coating increases your visibility at night. In testing, we confirmed that the adjustable belt doesn’t fit riders with waists narrower than about 30 inches (Hiplok notes this on its website), and even riders with 32-inch waists might experience slippage. Our main tester has a 34-inch waist and although the belt cinched tight enough, the heavy chain became uncomfortable after an hour in the saddle. For shorter commutes, though, we loved its convenience and high security.

Hiplok Spin

Weight: 1.7 lb. | Frame mount? No | Locking mechanism: 4-digit combination barrel

Hiplok Hiplok Spin $49.99 SHOP NOW amazon.com Comfortable while riding

Keyless entry Not as secure as bigger chains

The Hiplok Spin is the Gold’s little brother, and we found it significantly more comfortable to wear while riding. It also fits smaller waists, down to 26 inches, and bigger waists up to 44 inches. Its 6mm hardened-steel chain and hardened shackle are narrower than heavier chains, but it’s hefty enough to scare off casual plunderers. Similar to the Gold, an adjustable hook-and-loop closure allows you to don the lock without unlocking it.

OnGuard Mastiff

Weight: 12 lb. | Frame mount? No | Locking mechanism: Slider



OnGuard OnGuard 8019 Mastiff Chain, $109.95 SHOP NOW amazon.com High security

Good value Very heavy

The Mastiff is an absolute brute of a lock, heavier than most cyclists want to carry (although we didn’t mind schlepping it around on an e-bike). The 3.5-foot-long chain uses 10mm-thick, titanium-reinforced steel links that are hexagonally shaped to make cutting even more difficult. (The Mastiff ran down the battery of our tester’s cordless angle grinder when we attempted to cut one in 2013.) The company’s tough Boxer U-lock secures the chain at each end. A nylon sheath keeps the chain from scratching your frame. For an extra $15, you can purchase the anti-theft protection program , which covers your bike (assuming you’ve locked it up properly ) for three years.

Kryptonite Evolution Mini

Weight: 5.8 lb. | Frame mount? No | Locking mechanism: Disc detainer

Kryptonite Evolution Mini Lock, $88 $92.95 SHOP NOW amazon.com Integrated locking mechanism saves weight Not as secure as using the same Kryptonite chain with a corresponding U-lock

The integrated Evolution combines the locking mechanism with the chain, forgoing the need for a connecting U-lock and therefore saving weight. The 10mm, six-sided chain links resist cutting, and the disc detainer locking mechanism is designed to resist picks and drills. Kryptonite doesn’t consider the design as secure as its U-lock-equipped chains, but the company still offers $3,000 of anti-theft protection for buyers who register their bikes (the coverage is free for the first year, after that it’s $10 per year or $25 for five years).

Bell QuickZip Combo (2 pack)

QuickZip Combo Lock Bell amazon.com $13.99 SHOP NOW Lightweight

Excellent value Easily cut with shears or snips

These Bell zip tie-type locks are available at Target and on Amazon, and you can have two for less than the price of Hiplok’s Z Lok. The lightweight locks are nearly identical in weight and size—the Bell lock is about 2 inches longer—and both use a three-digit combination. We found that the number wheels on the Hiplok spun more easily than the Bell lock, but that was the only perceptible difference. The locks have identical cores as well, a thin metal band. Both locks withstood cutting attempts from household scissors, and both failed immediately when faced with a decent pair of wire cutters or metal shears.

Hiplok Z Lok Combo

Weight: 0.2 lb. | Frame mount? No | Locking mechanism: 3-digit combination



Hiplok Z Lok Combo $24.99 $20.99 (16% off) SHOP NOW amazon.com Extremely lightweight

Cheap Minimal security

This minimalist lock operates like a big zip tie, cinching in place with a three-digit combination. The 3.6mm tie has a steel core sheathed in plastic that doesn’t offer much protection from hand cutting methods—we got through it with tin snips. But it’s ideal for stashing in your jersey pocket and tethering your bike to a pole while you pop inside the coffee shop.

Ottolock Cinch

Weight: 0.5 lb. | Frame mount? Optional | Locking mechanism: 3-digit combination

Ottolock Cinch Ottolock competitivecyclist.com $55.00 SHOP NOW Lightweight, portable

Keyless entry Can be cut with hand tools

The Ottolock Cinch offers solid security for quick trips into the store (the company indicates it’s not for long lockups or high-risk areas). The 0.5-pound lock uses a Kevlar and steel band to prevent cuts, and the whole thing coils up to a 3-inch-diameter package that stows away beneath your saddle rails. Although not a replacement for a traditional U-lock, it’s smaller and more durable than a cable, making it a convenient upgrade. And the company sells a mount for your frame or seatpost for an additional $25.

Bike lock manufacturers use a few popular mechanisms with varying levels of security. Lock picking is an acquired skill, and anecdotal evidence indicates that destructive attacks are much more common. Likewise, an expert with the right tools can get through any bike lock pretty quickly—see LockPickingLawyer or Bosnianbill for a master class in advanced bike lock picking. Thankfully, most thieves aren’t expert locksmiths with custom tools, but amateurs can still foil a couple of prominent lock designs with fairly basic attacks. We consulted lock-picking expert, Schuyler Towne, to break down the prominent locking mechanisms in order of most to least secure.

Disc Detainer

Also called disc-tumbler locks, these locking mechanisms use a series of slotted rotating discs separated by washers. Each disc has a cutout; when locked, the cutouts don’t line up, but inserting and turning the key rotates them into alignment to form a channel. A sidebar rests against the discs, preventing you from turning the lock when there’s no channel for it to drop into. Therefore, opening a disc-detainer lock means aligning each individual disc to a relatively precise position, which usually proves more difficult than picking other lock designs. Disc-detainer mechanisms are popular on bike locks because they’re fairly secure and because they don’t contain springs and can be manufactured to low tolerances, two factors that mean they continue to work after years of use.

Slider

In a slider lock, inserting a key actuates a series of springless sliders within a plug that correspond to a slot on the outside of the plug. Riding atop the sliders in the slot is a sidebar, which must fall into the slot before the lock can turn. With the key inserted and the sliders in their correct position, the sidebar falls into the slot and the plug turns within the cylinder. These locks can be high or low security, depending on their construction and number of sliders.

Pin Tumbler

This lock has a plug that sits within a cylindrical housing. The plug and housing contain long pin chambers that allow a series of pins that are spring loaded to move back and forth between the plug and the housing. While locked, pins sit right in between the plug and the housing, preventing the plug from turning. When the key goes into the plug, it lifts up the spring-loaded pins so that they move completely into the plug or housing, leaving a gap between the two that allows the plug to turn. These locks are susceptible to skilled pickers who can depress each individual pin, but they can also be raked, which requires less skill. A “rake” is a pick with a specially designed tip that, when raked across the wafers or pins rapidly, can set them and turn a lock without a key.

Wafer