The best alarm clocks you can buy

Even if you sleep like the dead, you'll spring back to life at the first blast of the crazy-loud alarm, vibrations, flashing lights, and bright red display of the Sonic Alert Sonic Bomb Alarm Clock.

Now, this is an alarm clock for the heaviest sleeper. If you're the type who sleeps through anything — thunderstorms, loud neighbors, earthquakes, the zombie apocalypse — you've finally met your match. Sonic Alert's Sonic Bomb Alarm Clock doesn't just rely on its 113-decibel alarm to pry your eyelids open (for comparison, that's about the same decibel level as a car horn or snow blower going off in your ear), it also has a shaker device that slips underneath your mattress or pillow to jiggle you awake, and red flashing lights that trigger with the alarm.

You don't have to use all of those features, however. You can set them in a variety of combinations, or even turn all of them off except for the flashing red lights. You can also set the length of the alarm's ring from one to 60 minutes, and choose a snooze option from one to 30 minutes. Plus, the clock has dual alarms, so both you and your partner can have different wake-up times.

Health chose the Sonic Bomb as one of the best alarm clocks for heavy sleepers, commenting that the flashing lights, loud sound, and bed shaker should "deliver the full sensory message that grave danger awaits unless you get out of bed."

With nearly 7,000 customer reviews on Amazon, the clock has an average of 4.1 out of 5 stars. Not only do most buyers comment that it easily awakens them even though they are heavy sleepers, but several hearing-impaired buyers also mentioned that even without the sound, the vibration and flashing lights were enough to wake them up. One user summed it up well: "If you can sleep through this, then you may not be alive."

Pros: Multiple features to wake up the heaviest sleeper, good for those with hearing impairments, available in several different colors

Cons: A bit cheesy looking, overkill if you're not a deep sleeper

Buy the Sonic Alert Sonic Bomb Alarm Clock on Amazon for $32.29 and up (price varies by color)

If harsh, buzzing alarms aren't your preferred way to greet the new day, the sunrise simulation and gentle nature sounds of the Philips Wake-Up Light are a far more relaxing way to slip out of your slumber.

The Philips Wake-Up Light offers a choice of five pleasant nature sounds — or for the more traditionally minded, FM radio — for your morning wake-up call, but the real star of the show is the sunlight simulation. Twenty to forty minutes before your programmed wake-up time (you set both times), the clock will slowly begin to simulate the sunrise, complete with the softest dawn reds and oranges gently brightening into sunny, yellow light.

Once full "daylight" is reached — you can customize the intensity of the light with ten settings — the nature sounds will chime in as well. You can hit snooze for an additional nine minutes of sleep, but the sunrise will remain on. The Philips Wake-Up Light has dual alarms, so you and your partner can each set a wake-up call.

The Wake-Up Light also works to help you fall asleep, with a reverse "sunset" feature. The lights will slowly dim, lulling you into a restful sleep. You can also use the clock as a bedside lamp while you read.

The Philips Wake-Up Light is a top-pick on many consumer websites. Digital Trends praises the clock's ability to wake you slowly and gently, thus setting your mood for a more pleasant day.

The Wake-Up Light is relatively popular with Amazon buyers, also, with more than 4,000 reviews and an average of 4 stars. Customers love the gentle sunrise, but there are some complaints, as well. Many people mentioned that the buttons are not conveniently placed, and others felt the time readout was not large enough.

Pros: The sunlight simulation is a far more pleasant and natural way to wake up, can be used as a bedside lamp, sunset simulation to help you fall asleep

Cons: Buttons are poorly positioned, pricey

Buy the Philips Wake-Up Light on Amazon for $104.99 (originally $139.99) Check out our guide on the best wake-up light therapy alarm clocks

With the ability to pull content from the internet and control your home, Lenovo's Smart Clock with Google Assistant changes the way an alarm clock wakes you up.

The Lenovo Smart Clock is more of a bedside assistant than an alarm clock. Yes, it will show you the time on the 4-inch touch-capable display, and you can set multiple alarms. But because it's connected to the internet, you can use this gadget to check weather and traffic before you start the commute; catch up on info like news, sports, and stocks; play music from Spotify, podcasts, or NPR; check your Google Calendar; and, with support for Google Home and Google Assistant, you can control the smart home devices in your home, from Philips Hue lights to Nest Thermostat — all of these by using your voice.

The clock is compact and doesn't take up much room on a bedside table. Its fabric exterior also gives it a soft touch, which is something you wouldn't find with most alarm clocks (or tech product, for that matter).

As an alarm clock, the device doesn't simply blare at you with a buzzer (although that's available too). The screen slowly brightens — like a light therapy clock — and you can customize the sound for each alarm, or wake up to music or news. Even smarter (hence its name), you can automate a specific wake-up routine that turns on lights, set the temperature, and whatever else is connected to your smart home setup. At night, the screen goes dark to help you sleep, while the USB port lets you connect a phone for charging.

Setting it up is easy, although you will need a smartphone with the Google Home app (Android or iOS) to do this (the touchscreen is limited in what you can do). It's relatively painless — just launch the app, and the Smart Clock is automatically recognized and guides you through the set-up process. This is technically a smart speaker, but if you're paranoid about it always listening (like I am) there is a mute toggle on the back; thankfully, there's no camera, which seems to be showing up in every smart home product these days.

There are a few things that the Smart Clock can't do. It can't play videos, so don't think about watching YouTube on this thing to help lull you to sleep; nor can it make calls, like you can with the similar Echo Spot from Amazon, a smart clock based around the Alexa platform. Even though the Smart Clock has Bluetooth, you can't use it to play music from your phone, but you can use Google Chromecast to stream audio to another connected speaker or TV. If you desire the abilities to watch YouTube videos or display content from Google Photos and other "smarter" functions, you may want to look at larger smart displays, like the Google Nest Hub.

As an alarm clock, we like the design, lower price, and tight integration into Google's services of the Smart Clock over Amazon's Echo Spot. If the price was even lower, we wouldn't hesitate to call this our best overall — because, for the first time, you can actually do more with an alarm clock than just wake you up.

Reviews are generally positive, and the criticism — the inability to play videos or and photos, make calls — is in line with ours. Both Wired and The Verge are a little harsher, citing the poor audio quality from the speaker. Insider Picks Senior Editor Malarie Gokey has been testing one by her bed, and she appreciates the size and the variety of alarm sounds. If this product had been priced above $100, we would have passed on it, but considering what it can do and for the price, we still think it's a good buy despite the drawbacks. This is a first-gen product, so expect to see newer and improved versions. — Les Shu

Pros: A variety of wake-up options, display mimics a light therapy clock, supports most Google services and Google Assistant, play from Spotify, Pandora, podcasts, and other online services, control your smart home devices, compact size, elegant design, easy to set up, affordable, USB port for charging

Cons: Can't make calls, play videos or photos, can't stream music from phone, audio quality could be better, Google Home platform required, phone is needed for set-up

Buy the Smart Clock with Google Assistant from Lenovo for $79.99

If you prefer the old-school simplicity of an analog alarm clock, you can't go wrong with the travel-friendly Marathon Analog Desk Alarm Clock.

Perfect for those who prefer a small and simple bedside clock, or need something easy to slip into a suitcase, the Marathon Analog Alarm Clock comes in several colors, is completely silent, has an auto-on soft nightlight that triggers in low light, and a big, spring-loaded button on top to simplify setting or turning off the alarm. It reminds us of the beautiful and iconic Braun Classic Analog Quartz Alarm Clock, but it has a few more useful features.

If you wake up in the middle of the night and want to see the time, a simple push of the snooze button on top of the clock gives you just enough light to easily read the large numbers.

The Marathon clock more than 600 customer reviews on Amazon, with an average of 4.7 stars. Buyers like the clock's completely silent performance, durable construction, soft backlight, and convenient size. The clock's nonslip bottom is another handy feature that buyers liked.

At roughly 4 inches by 4 inches, the clock is just large enough for easy visibility, won't take up much room on your nightstand, and is small enough for travel. It runs on two AA batteries, which are included.

Pros: Silent performance, several color choices, easy to use

Cons: Batteries will eventually require changing

Buy the Marathon Analog Desk Alarm Clock on Amazon for $29.95 (originally $39.95)

With OK to Wake! Alarm Clock on the nightstand, your toddler will know when it's time to get up, and when it's time to stay in bed.

It's a familiar scenario to most parents of young children: Your little one toddles into your room — or starts cruising around the house — far earlier than you'd like. If you're at your wits end for lack of sleep, Ok to Wake! could be the solution you're so desperate for.

This cute alarm clock shows the time just like a regular clock, and can also function as a nightlight for up to two hours. It has a regular beeping alarm, which can be set for any time you would like, and a nap alarm, which functions as a timer to gently wake your child after your desired nap length.

But where OK to Wake! really shines (pun intended) is in its unique feature that parents love: the clock will glow green and show a cute face when it's an acceptable time for your little one to get out of bed. That means even very young children can learn when it's okay to go looking for mommy or daddy — no need to be able to actually read the time. As your child grows, you can stop using the glow feature, and simply use the device as a regular, albeit cuter than average, alarm clock.

It's not perfect, however. The biggest complaint from Amazon buyers is that the clock runs through AA batteries very quickly if you don't have it plugged in (USB adapter sold separately). Still, if you have a youngster who wakes up before the dawn, this may be your solution.

OK to Wake! comes with two faces: a purple flower and green bug. It's easy for kids to use; they simply touch one foot to silence the alarm, the other foot to turn the nightlight on and off. The controls for changing the time and setting the alarm are concealed in the back so your toddler's little fingers can't reset them accidentally.

Pros: A great way to help young children learn to use a clock and determine when it's okay to get out of bed

Cons: Wears out batteries quickly, does not include electrical plug, best for kids kindergarten-age and younger

Buy the OK to Wake! Alarm Clock on Amazon for $24.55