The 10 Best Bike Alarms
Updated by · How we research
Bike alarms are a loud backup, not a lock. We compared 10 sirens, alarmed disc locks and alarm locks, and the WSDCAM Wireless Bike Alarm comes out on top. When users buy our independently chosen editorial choices, we may earn commissions to help fund the Wiki.
A bike alarm won't hold a bike in place. It makes noise, so it works as a warning on top of a real lock, not as a stand-in for one. This list covers stick-on sirens, disc-brake locks that scream when touched, a hidden alarm that doubles as a tracker and full locks with alarms built in, for commuters and e-bike riders.
Editor's Notes
November 1, 2026, by Ezvid Wiki Admin:
The WSDCAM Wireless Bike Alarm stays at the top. It's cheap, quick to fit, and it lets you turn down both the volume and the sensitivity, which is what keeps an alarm from crying wolf on a windy rack. The YOHOOLYO LK603 and the ABUS Bordo Alarm also stay. The G Keni tail light alarm is gone, and older disc locks, a U-lock and a cable lock gave way to current ones we could document better.
New picks cover a rechargeable siren, the URBAN UR6 with its warning beeps, a Kryptonite disc lock, an alarmed U-lock for fat-tire e-bikes and Knog's hidden alarm that reports to Apple's Find My. No lab or magazine test of bike alarms turned up, so loudness and range figures come from makers and sellers, set against a roundup of seven sirens that measured some remotes well short of their claims. We checked every brand against U.S. Consumer Product Safety Commission recalls and found none for these models.
December 02, 2020:
The items in this list fall roughly into three categories: alarms that light, alarms that lock, and alarms that sound only. Some people will need both an alarm and a lock in one, while others may want to keep these idea separate, concealing the alarm under a saddle or disguising it as part of a lamp.
If you already have a way to secure you wheels, the WSD Cam Wireless is an inexpensive alarm that can be operated remotely with plenty of sensitivity modes to stop it being triggered too easily. Alternatively, you could combine your alarm with a taillight by purchasing either the Onvian 2-In-1, or the G Keni A6, both of which come with a remote control and feature multiple light modes.
If your bike has a brake disc, then you can prevent it from being wheeled away by attaching either the Jacool Disc Brake Lock, or the Yohoolyo LK603, both of which come with reminder cables to stop you absentmindedly trying to pedal away with them still attached.
Most people will probably want to combine their alarms with a lock if they can, keeping their security solutions simple. If you like U-locks, then the Oxford OF3 Boss will take some beating for indestructibility, although it doesn't come with any means for mounting it to your bike, unlike the Crystal Vision U-Lock that hangs neatly under your toptube as you ride.
If you prefer cable locks, then the Wsdcam Cable Lock or the Nunet Nulock are your best bet. The former has a remote control while the latter uses Bluetooth to connect to your smartphone app.
Finally, we added the Abus Bordo Plus as a solid (but rather pricey), folding lock option that won't go off while you're traveling with it mounted to your seat tube, and folds out to create quite a large locking area.
April 30, 2019:
When evaluating the best bike alarms we included models that double as a bike lock and choices that only function as an alarm because those tend to have other useful features like the G Keni A6 that also adds a rear taillight that can flash.
While the Bluetooth-enable Nunet Nulock contains some of the most advanced technology of the bunch, we didn't rank it first because simplicity is sometimes better, especially if you're the kind of person who doesn't keep your phone fully charged at all times.
The WSD Cam Wireless does not double as a lock, but it's still ranked first for being the only choice to offer adjustable sensitivity levels for users who are worried about disturbing neighbors for false alarms, and it's unobtrusive design.
Three Kinds Of Bike Alarm
Alarmed U-locks and cable locks exist at lower prices, but a cable is the weakest of the three.
The simplest is a stand-alone siren: a small box that sticks, straps or clips onto the frame and goes off when the bike is shaken or moved. Most cost less than a lock, come with a key fob to arm them, and also work on scooters, trailers and sheds. An independent roundup of seven sirens found most run between about 90 and 113 decibels, with seven sensitivity steps as the norm.
An alarmed disc lock pushes a steel pin through a hole in the brake rotor so the wheel can't turn, and its siren sounds when the lock is disturbed. It only fits bikes with disc brakes, and the pin has to clear the rotor's holes: Kryptonite's pin is about 6 millimeters, many others about 7.
A lock with an alarm built in does both jobs. The ABUS Bordo Alarm 6000 folds out into a chain of hardened bars, and ABUS rates it 10 on its 15-step security scale (Ruff Cycles). Alarmed U-locks and cable locks exist at lower prices, but a cable is the weakest of the three.
A fourth route is a tracker that also beeps. The Knog Scout hides under a bottle cage, sounds an 85-decibel alarm and reports its spot through Apple's Find My, so it only works with an iPhone.
Setting It Up So It Doesn't Cry Wolf
False alarms are the fastest way to end up with an alarm you never arm. Start with the sensitivity low and raise it one step at a time, especially in wind, near traffic or on a shared rack where other riders bump your bike. Turn the volume down on quiet streets; full blast is for busy downtown racks.
Mounting matters. A bracket holds better than double-sided tape, and a strap fits more frame shapes. A visible alarm warns a thief off; a hidden one surprises them, and it's harder to rip off.
Watch the power. Rechargeable alarms charge over USB-C and, by makers' claims, last one to three months; coin-cell and AAA models need fresh batteries on hand. A low-battery beep is worth having. The same roundup also found real-world remote range can fall well short of what sellers claim, so arm the alarm before you walk far.
Disc locks carry one real hazard: riding off with the lock still on can stop the wheel dead and throw you. Use the coiled reminder cable that runs to the handlebar, or pick a lock with warning beeps like the URBAN UR6.
An Alarm Is The Backup, Not The Lock
People have been wiring alarms to vehicles since at least 1913, when an early car alarm was patented (Wikipedia). The idea hasn't changed: noise draws attention, and a thief who hears it usually moves on. It does nothing against someone who doesn't care, or who has a van and a minute.
So lock the bike properly first. Sheldon Brown's long-standing locking guide suggests a U-lock around the rear rim and through the rear triangle of the frame, plus a cable for the front wheel, because each needs a different bulky tool to defeat. Lock to a post or rack that can't be cut, unbolted or lifted over.
Then add the alarm. A siren on the frame or a disc lock on the rotor costs little and makes a quick grab noisy. If the bike is valuable, a hidden tracker gives you a way to find it if the rest fails. None of the brands on this list had a recall on file with the U.S. Consumer Product Safety Commission (SaferProducts.gov) when we checked.
How we researched this
We compared 18 bike alarms and alarmed locks, read makers' and sellers' specifications, an independent roundup of seven sirens, lock-maker security ratings and a long-standing bike-locking guide, and checked every brand for recalls with the U.S. Consumer Product Safety Commission.
Frequently asked questions
Are bike alarms worth it?
As a cheap extra on a good lock, yes. A siren makes a quick theft noisy and tells you something is wrong. On its own it holds nothing, so a determined thief can still cut a lock or carry the bike off.
What is the best anti-theft setup for a bike?
A solid U-lock or folding lock through the frame and rear wheel, locked to something fixed, plus an alarm or a hidden tracker. Cable locks alone are easy to cut.
Will an alarm disc lock fit my bike?
Only if the bike has disc brakes and the pin fits through the holes in the rotor. Check the pin size against your rotor before buying. Rim-brake bikes need a stand-alone siren or an alarmed lock instead.
How do I stop my bike alarm from going off by itself?
Lower the sensitivity a step at a time, especially in wind, near traffic or on a shared rack. Mount it firmly so it doesn't rattle, and lower the volume where a false alarm would bother neighbors.
How long do bike alarm batteries last?
Makers claim one to three months per charge for rechargeable sirens and up to a year for some disc locks with replaceable cells. Arming the alarm every day shortens that.
Can I use a bike alarm on an e-bike or scooter?
Yes. Stand-alone sirens mount on any frame, and alarmed disc locks fit e-bikes and scooters with disc brakes. Fat-tire e-bikes need a wide U-lock.
