To determine the best car alarm, we looked at the following key features: sensors, one-way versus two-way, installation, engine shut-off, and value-added features. You’ll need to consider sensor style, as you can choose between vibration, pressure, or a combination of the two. If you want confirmation for any buttons pressed beyond a simple LED light, then a two-way car alarm is a better choice. Self-installers should look for car alarms that come with a complete installation kit and ensure that the alarm they want is compatible with their car. And finally, additional features like engine shut-off or remote starting can improve the functionality of your car while also preventing thieves from driving off in your car.
After reviewing all of the above, we nominated the Viper 350 PLUS 3105V 1-Way Car Alarm as our Top Pick. This is a brand that most people recognize as a leader in the car protection niche. More importantly, this particular alarm comes with Viper’s patented FailSafe Kill anti-theft feature that prevents the engine from starting when it detects a break-in. Keep reading to learn more about the rest of our top picks.
Top 6 Best Car Alarms
#1 Viper 350 PLUS 3105V 1-Way Car Alarm
Award: TOP PICK
WHY WE LIKE IT: A top industry recommended option that features anti-theft FailSafe Kill and an easy installation system makes this model the best car alarm.
Read Full Review: Viper 350 PLUS 3105V 1-Way Car Alarm
- Starter killer (key must be present)
- Easy to install
- Includes 2 key fobs
- 1-way car alarm
- Remote start & GPS require upgrades
For as long as car alarms have been popular, Viper has consistently been one of the most recommended brands in this automotive category. We’ve nominated their 350 Plus 3105V 1-Way Car Alarm as our Top Pick because we think it’s the best car alarm within the one-way design category. We like that this recommendation comes with a complete installation kit that includes all of the wiring you’ll need along with two key fobs, the alarm, and the receiver.
But more importantly, we like the Failsafe Kill anti-theft feature. It ensures that you can prevent the engine from being started and thwart thieves from stealing your car. Plus you’ll like that there’s a visible blue status LED that would-be carjackers can see — encouraging them to look elsewhere. And the six-tone soft-chirp alarm relies on shock sensors that emit sounds in a range of tones depending on the vibration intensity it detects. You can also have a look at the best car battery charger.
#2 Avital 3100LX 3-Channel Keyless Entry Car Alarm
Award: HONORABLE MENTION
WHY WE LIKE IT: A smart car alarm with an anti-theft starter feature that relies on dual-zone sensors to prevent false alarms — making it perfect for car owners that don’t want false alarms to annoy their neighbors.
Read Full Review: Avital 3100LX Car Alarm
- Prevents false alarms & keyless entry
- Anti-theft Starter interruption
- Dual-zone impact sensors
- 1-way car alarm
If you remember car alarms from the 1990s, they were notorious for being ultra-sensitive to the point that thunderstorms or even a stray cat walking too close to your car could set them off. If this has made you shy about installing an aftermarket car alarm, then the Avital 3100LX 3-Channel Keyless Entry Car Alarm will put those fears to rest.
This one-way alarm is designed with a dual-zone impact sensor to detect between minor vibrations versus full impacts or blows to your car. But best of all the Nuisance Prevention Circuitry helps to prevent those annoying false alarms that drive you and your neighbors crazy. You’ll also like the anti-theft starter interrupt feature that prevents hot-wiring attempts. You also get two keyless entry fobs that feature three buttons and an LED light indicator, great for older model cars that are compatible. Once you get your alarm set up, check out the best car stereo
#3 CarLock 2nd Gen Advanced Real Time 3G Car Tracker & Alert System
Award: BEST FOR TEENAGERS
WHY WE LIKE IT: An app-based OBD car alarm that notifies you if your car has been moved, if someone is driving aggressively, and monitors your car’s diagnostics — creating an intuitive car monitoring and alarm system that’s ideal for modern times.
Read Full Review: CarLock 2nd Gen Advanced Real Time 3G Car Tracker Review
- Easiest installation
- Syncs with smartphone app
- Virtual mechanic car diagnostics monitoring
- Lacks starter kill feature
These days, people want to be able to control everything directly from their smartphone. And that’s why we included the CarLock 2nd Gen Advanced Real Time 3G Car Tracker & Alert System in our guide. This is a great option because it’s a car alarm that notifies you of any activity happening in and around your car. Plus of all the options in our guide, this is by far the easiest one to install since you only need to insert the included receiver into your car’s on-board diagnostic port and pair that with your smartphone.
Although this alarm lacks a starter kill feature, we like that it sends automatic alerts to your smartphone when vibration has been detected, your engine has been started, and when your car is moving. But this is also a great tool for parents of new drivers since you can also monitor multiple cars with this device. This means you can tell if your teen is engaged in distracted driving, driving too fast, or even if they’re engaged in risky behavior like drag racing. And best of all, this car monitoring system also acts as a diagnostic, alerting you when it’s time to take your car in for service. Speaking of practical car accessories, the best car floor mats will help keep your vehicle clean.
#4 Compustar CS7900-AS All-in-One 2-Way Car Alarm
Award: LOUDEST SIREN
WHY WE LIKE IT: A responsive two-way car alarm with support for a range of sensor placements and a loud 105-decibel alarm makes this the best car alarm for vandalism.
Read Full Review: Compustar CS7900AS All in One 2 Way Car Alarm Review
- 3,000ft remote start range
- Comprehensive sensor detection
- 105dB alarm siren
- Most expensive price tag
- All installation parts not included
What good is a car alarm if no one can hear it? The Compustar CS7900-AS All-in-One 2-Way Car Alarm is perfect for scaring away would-be thieves because it emits a startling 105-decibel alarm siren. For this reason, we think it’s the best car alarm for vandalism. You’ll also note that this is the only two-way car alarm in our guide, making it ideal if you want the peace of mind that comes from a remote system that provides audible or visual confirmation that the command buttons you’ve pressed are properly activated.
We like that this model also features a remote start that can be activated up to 3,000 feet away from your car and an LCD remote. This system also supports a comprehensive sensor detection placement, including in your trunk, hood, and doors. But you can add impact sensors to wherever you need them. And if for some reason you lose the LCD remote, this car alarm comes with a backup one-way remote with an LED light indicator. You may also like the best car subwoofer for your ride.
#5 Crimestopper SP-402 Car Alarm
Award: BEST QUALITY
WHY WE LIKE IT: A comprehensive one-way car alarm that comes complete with remote start and engine disabling functionality — making it the most well rounded one-way model in our guide.
Read Full Review: Crimestopper SP-402 Car Alarm Review
- Kill switch & remote start in one package
- Smartphone integration capable
- Anti-theft engine disable
- Enhanced features require upgrades
A common issue we found while researching options for our buying guide was that often one-way car alarms force shoppers to choose between the remote start or engine disabling. Usually only one of these features is standard and the other must be added on with a separate purchase. But the Crimestopper SP-402 Car Alarm gives you both of these important features and is also fairly easy to install.
We like that you can remotely start your car as far as 2,300 feet away from the vehicle. While that isn’t as far as our #4 pick, this is still a great feature. This model is designed to support smartphone integration so that you can manage your car’s security from anywhere — although the models must be bought separately. And even though the enhanced functionality beyond remote start and engine shut-off requires separate upgrades, the fact that you can turn this alarm into a two-way alarm is impressive. An alarm takes care of your vehicle security, but for comfort check out the best car seat cushion.
#6 InstallGear Car Alarm Security & Keyless Entry System
Award: BEST BUDGET
WHY WE LIKE IT: A simple and affordable one-way car alarm that’s easy to install and is compatible with any car that features powerdoor locks.
Read Full Review: InstallGear Car Alarm Review
- Universal power-lock car compatibility
- Complete installation system (professional installation not required)
- 2 remotes with LED indicators
- Best value/budget option
- Vibration sensors only
To be honest, most cars made within the last 20 years drive off the factory assembly line with alarm systems already installed. So, unless you have a faulty factory alarm, you’re probably not looking for a car alarm unless you’re driving an older car. And because of that (depending on the car) you might not want to buy one of the more expensive options in our guide. The InstallGear Car Alarm Security & Keyless Entry System is an all-in-one solution that won’t leave you cash strapped but will still give you the confidence you need when you’re not in your car.
This car alarm is designed to work with any car that offers power-lock doors. So, keep this in mind if you were thinking of using this car alarm for a classic car as it might not be compatible. You’ll like that this one-way alarm comes with the complete installation kit and two key fobs that include an LED indicator light and provide keyless entry and trunk controls. While it lacks remote starting or even engine shut off, this is a great basic car alarm for budget shoppers. Also read about the best car diffuser.
How We Decided
Car alarms are usually a standard feature on most modern cars. But if you have an older car or for some reason need to replace a faulty factory car alarm and you’re no longer in warranty, buying an aftermarket car alarm boasting the best features the market has to offer is going to be important. To create our guide of the best car alarm systems, we considered the following features — sensors, one-way versus two-way, installation, engine shut-off, and value-added features.
The first feature we reviewed was one-way versus two-way alarms. One-way alarms tend to be cheaper options but don’t give you the responsive confirmation that verifies that whatever buttons you pushed have activated a function within your car. Only our Best Quality recommendation is a two-way alarm, with our Top Pick, Honorable Mention, #4, and Best Budget being one-way car alarms. And our #3 model is a smartphone-enabled car alarm and monitoring service.
You’ll also need to consider the sensors. All of our recommendations rely on sensors of some kind, but whereas the one-way models tend to focus on vibration or shock sensors, others like our #3 and Best Quality also support module receivers that can plug into your car’s on-board diagnostic port in the dashboard to create a smartphone link for truly remote management. Also, keep in mind that some systems may require you to purchase and install additional sensors if you’re hoping for a 360-style car alarm security system.
Ease of installation is also important — especially if you’re thinking of installing a car alarm system on your own. By far, our #3 recommendation is the easiest one to install. However, all of our one-way and two-way recommendations come with complete installation kits.
Two key value-added features that many people want in a car alarm include a remote start system and engine shutoff (also known as starter kill). These features aren’t always standard, or one of the two will come standard with an alarm system while the other must be upgraded later for an additional expense. However, our Best Quality recommendation does include both of these features and is also a two-way alarm that can be further upgraded to include smartphone integration.
You can also check out our review of the Python 5706P Responder LC3 SST 2-Way Car Security System.
Best Car Alarm Buyer’s Guide
The Most Important Factors to Consider
Even though most modern cars come with a built-in alarm system, if you’re planning on installing a car alarm on an older car or upgrading your current system, you’ll want to think about the sensors. There are multiple ways that someone can attempt to steal your car. Obvious options include tampering with your car’s door locks or simply smashing a window. But you’ll want a car alarm system that offers multiple sensors so you can guard the most commonly breached areas — doors, windows, and even the trunk or hood. Look for systems that feature pressure and motion sensors.
- One-way vs. Two-way
For most people, their car key fob doesn’t offer an audible confirmation when the doors have been locked or the alarm has been set. The only way to know this is to be physically in front of your car while you press buttons on your key fob. But a good aftermarket car alarm system should include a two-way remote. These remotes provide confirmation either by illuminating or creating message notifications (either text or audible) when the desired action has been completed.
- Ease of Installation
If you’re looking at aftermarket car alarms and are planning on installing them yourself, you’ll need to consider how complex or easy the task may be. If you’re not well-versed under the hood, then take your system to a professional and have them install it. This will add to your cost, but it’s better to have something done right. But if you’re more confident in your installation capabilities, you’ll want to confirm that the alarm system you’re selecting won’t put a burden on your car battery.
- Transmission Encryption
While some people may still try to steal a car the old fashioned way, car thieves are getting smarter these days. That means that they can attempt to hack their way into your car by disarming your car’s alarm system remotely — and then conveniently entering your car and driving away. To prevent this, look for car alarm systems that feature encrypted transmission.
- Mobile Apps
Unsurprisingly, people want everything they use to have seamless functionality. And in many cases, that means syncing your car’s alarm system to a mobile app. This can make life a lot easier because you’ll be able to access the same functionality (and sometimes more) that you would through a traditional remote. But depending on your budget, you can also find car alarms with compatible apps that let you manage other important features like managing diagnostics that let you know when it’s time to take your car in for service.
Best Car Alarm FAQs
Are car alarms worth it?
The short answer is yes. However, when we dig deeper, we find that car alarms are a worthwhile investment when used in conjunction with other technology like vehicle recovery systems or immobilizers. While a very determined thief won’t be deterred by most standard car alarms, the added protection of the noise, and the risk of discovery will be ideal for making the average car thief think twice before stealing your car.
What triggers a car alarm?
Car alarms are triggered when their sensors detect activity. Depending on the type of sensors your car alarm uses, that activity could range from pressure (such as detecting sensations on windows or doors) to motion, or even a change in voltage that indicates someone has opened a door or the trunk because the interior lights are activated.
Why do car alarms go off for no reason?
Although this isn’t as big of an issue as say in the 1990s when car alarms were still a new novelty with a few kinks in the design, there are a few common culprits behind this. One issue could be a faulty key fob that is malfunctioning and sending the activate alarm signal to your car’s alarm even when you aren’t pressing the alarm button. If you suspect this is an issue, consider changing the battery on your key fob. But a dying car battery can also be the cause of this annoyance. The easiest way to remedy this is to switch out to a new battery or find a good Samaritan with jumper cables to help give you a boost.
How much does it cost to install an alarm system in a car?
This depends on whether you are going to install a car alarm by yourself or if you’re going to have it professionally installed. If you’re confident in your skills, then the cost is going to depend on the alarm you pick. Based on our research, the price can range from as little as $30 to as much as $200 or more. But if you opt to have a car alarm professionally installed, the price could be significantly more and may vary depending on which installer you hire.
How do panic buttons (panic mode) in cars provide safety and security?
Panic buttons are used to alert people in a potential emergency. You simply press the button and an alert is sent to the police. In the same way that panic buttons can increase security and safety in your home, they also protect your friends and family in your car and alert the police during an emergency.
Learn More About Car Alarms
Read car alarm reviews to compare theft-preventing car alarms and be informed of the latest features in the best car alarms. These include code hopping that prevents thieves from capturing remote signals from the owner to the car alarm; immobilizers that are activated when the car alarm sounds; and additional features such as trunk release and GPS-enabled alarms (GPS tracking).
Car alarms can be divided into two main categories – passive and active systems. Do you know that you can even purchase silent car alarms? These do not blast a siren; instead they send a message to the owner. Gadget Review lets you know about the best car alarms out there manufactured by brands like Prestige, Viper, Avital, and Gravity. Car alarms not only serve as effective anti-theft mechanisms, they can also help bring down the cost of car insurance.