Personal safety alarms: what they are, 5 best

What makes the best personal safety alarms

Loud enough to matter: A siren of at least 130 dB, the level a self-defense instructor told NBC Select to look for.
Fast, one-hand trigger: A pull pin or button you can fire in seconds without fumbling your keys or phone.
Ready when you are: Rechargeable with long standby, or a low-battery warning, so it never dies quietly in a bag.
Light that helps: A strobe to draw eyes and a flashlight for dark streets, hotel hallways and night walks.
Small and trip-proof: Rides on keys, a bag or a door; no blade or spray, so it goes in a carry-on.

The siren can also distract, disorient or surprise an assailant, buying a moment to get away. Volume varies by model; some reach 130 dB.

Siren plus light: Many add an LED for everyday use or to help deter an attacker; Birdie 3.0 pairs its siren with a flashing strobe.
No training needed: A self-defense expert told NBC Select an alarm needs no training to use and is legal to carry.
Distance, not contact: She’s Birdie co-founder Amy Ferber told The Hustle that pepper spray needs you much closer to an attacker, while an alarm gets eyes on you.
Non-violent by design: She’s Birdie describes its alarms as a way to deter attackers without fighting.
Who makes them: She’s Birdie, Bellbird, Vantamo, Mace and BASU, maker of the Sound Grenade, sell alarms on their own stores.

Pull-pin trigger: On Birdie 3.0 you pull the top pin to start the siren and strobe, and push the pin back in to stop them.
Push-button trigger: Mace’s 130 dB alarm starts with one press of its front button and stops with a second press.
Pin plus button: Bellbird combines a pull pin with button control on the same alarm.
Door trigger: Birdie Box sits on a door frame and sounds its siren and strobe when the door opens; it must sit within 1/2 inch of the frame.
Rechargeable cells: Birdie 3.0 charges over USB-C; Bellbird charges over USB in about an hour.
Replaceable cells: Mace’s 130 dB alarm runs on one CR2032 coin cell; its older keychain model takes three LR44 cells.
Two speakers: Vantamo uses two dynamic speakers to sound its 130 dB twin sirens.

Keychain alarms: The most common form; Birdie 3.0 hangs from a solid brass keychain, and Bellbird and Mace also ride on keys.
Clip-on wearables: Birdie Disc clips to clothing, a bag or a dog leash and doubles as a running light.
Wrist-strap alarms: Bellbird includes wrist straps so the alarm stays on your hand.
Door alarms: Birdie Box guards a hotel, dorm or rental door; SafeWise’s travel pick is SABRE’s door-wedge alarm.
App-connected alarms: In 2022 She’s Birdie added Bluetooth alarms that share your location and connect you to 24/7 call support.
Silent-alert jewelry: invisaWear charms send silent alerts to chosen contacts with a double press and have no siren.

At least 130 dB: Martial artist Peter Tay told NBC Select to look for an alarm that is easy to set off and reaches at least 130 dB.
A quick release: He also stressed deploying it fast, without fumbling or dropping your keys.
Alarm run time: Bellbird states about 90 minutes of siren per charge; many makers do not state a figure.
Low-battery warning: Vantamo gives a low-battery notice; Mace’s alarm chirps every 4 hours when its cell runs low.
Strobe and flashlight: Bellbird’s LED reaches 26 feet; Birdie Disc offers solid white, flashing white or flashing red light.
An off switch: Birdie 3.0, Birdie Disc and Birdie Box each have an on/off switch.

In the carry-on: TSA allows devices with lithium batteries of 100 Wh or less in carry-on bags, and in checked bags with special instructions.
In a checked bag: The FAA says a rechargeable lithium device may be checked only if it is completely powered off and protected from accidental activation.
Spare coin cells: Alkaline and button cells may fly in either bag if protected from short circuit; spare lithium metal cells go in the carry-on only, at 2 g of lithium or less.
Unlike pepper spray: TSA bars pepper spray from carry-on bags and allows one 4 fl oz (118 ml) container in checked bags, with a safety lock.
In the hotel room: She’s Birdie says Birdie Box holds to a hotel or rental door with Command Strips and leaves no mark.
Night walks and runs: Clip-on models such as Birdie Disc add solid or flashing light so you are seen on dark streets.
The officer decides: TSA says the final call on any item rests with the officer at the checkpoint.

Not a shield: An alarm can give a false sense of security and so put its owner in danger.
False alarms: An NBC Select editor’s Birdie once went off without being activated.
Read the instructions: Another NBC Select editor who uses Bellbird recommends reviewing the instructions before you need it.
Hard on hearing: NIDCD lists sirens at 110–129 dBA and advises avoiding sounds that are too loud, too close or too long.
Keep it charged: Bellbird quotes up to a year on standby; charge a rechargeable alarm before it reaches empty.
Paid features: Reviewed found the Birdie+ app’s safety features required a subscription after a free trial.

2014: BlingSting begins making jeweled, hot-pink self-defense devices.
2019: Sisters Amy Ferber and Alison Peters make She’s Birdie’s first sales, to friends and family.
2022: She’s Birdie rolls out Bluetooth alarms with location sharing, 24/7 call support and a fake-call feature.
April 2023: Reviewed tests the app-linked second-generation Birdie+.
October 2025: NBC Select names She’s Birdie its editor’s pick and Bellbird its best safety alarm.
April 2026: SafeWise updates its guide with She’s Birdie as its overall pick.