An audio baby monitor will set you back £50 on average, while a video baby monitor will cost at least twice as much. A smart wi-fi baby monitor with an app will generally cost three times the price.
Is the extra cost worth it?
We've just published new reviews of baby monitors ranging in price from £35 to £270.
Our tests found that you don't always get what you pay for, but that some cheap baby monitors are surprisingly good.
For example, the rechargeable battery on one baby monitor's parent unit didn't even manage to last three hours, but another kept going for more than 15. This would free you up from having to remember to charge it daily.
Video picture quality also varies widely. In our tests some were incredibly sharp and clear, with accurate colours and a good frame rate, but others were fuzzy, blurred and so dark that you can barely see your child.
Below we've highlighted some of the latest audio, video and wi-fi monitors we've tested, so you can weigh up the pros and cons and see which is right for you.
This mounted wi-fi baby monitor is one of the most unusual we've come across, offering an unobstructed birds-eye view of your little one in his or her cot.
It's filled with features, including sound and motion sensors, as well as an entertainment system with a light projector, lullabies and audio books.
You can view your child on the supplied parent unit or remotely on your smartphone or tablet using the Hubble for Motorola Monitors app.
The cute animal-themed exterior of the Arlo Baby masks a very sophisticated camera that provides high definition 1080p HD footage of your little one.
It can be set to automatically record motion or sound-triggered events, and it will save them to your cloud library to be downloaded and shared for up to seven days.
There's no parent unit, so you'll need to download the Arlo App. You can share the footage with grandparents and other loved ones via a video feed online at your own secure url.
We found loads to love about this baby monitor. Take a look at our Arlo Baby review to help you decide if it's worth you investing in.
Some video monitor cameras have to be moved manually if you want to get a differently angled picture, but the Summer Infant Baby Pixel Monitor has 3x digital zoom and remote pan and tilt.
In fact, you can cleverly change the position of the camera to view different parts of your baby's room by simply tilting the parent unit up and down or side to side, giving you complete control over what you can see.
It comes with a basic wall mounting kit if you don't have an appropriate surface for it to sit on, and you can connect up to four cameras to one parent unit, which is useful if you have more than one young child to keep an eye on.
Currently only available at Argos, the Motorola MBP482 is less than half the price of most video monitors and it's the cheapest video baby monitor we've tested in several years.
Included in the price are a number of practical features usually seen on pricier monitors, including temperature sensors and a sound-sensitive light display to show you the noise level in your baby's room.
The diminutive camera has night vision and zoom, and the 2.4-inch parent unit is in colour, to help you see what your baby is up to.
Audio monitors are much cheaper than video baby monitors and generally the batteries in the parent unit last a lot longer.
The VTech DM12111 certainly is among the cheapest available, and it offers two-way talkback and lullabies, so you can easily soothe your baby without going in the room.
It has sound-sensitive lights, as well as a vibrating alert to let you know if your baby is crying, which is handy when the sound is turned down low or if you're doing a task that means you might not hear the monitor clearly.
Typically most baby units (the bit that stays in the nursery) run on mains power, but the Angelcare AC110 can also be powered using two AAA batteries. This is handy in the event of a power cut or if you want to use this baby monitor while travelling or when staying with friends and family.
The temperature is displayed on the parent unit, but at a glance you can see if your baby's room is too hot or too cold by glancing at the large LED ring on the baby unit, which glows blue (cold), red (warm) and white (just right).
How does this baby monitor fare for sound quality? Read our Angelcare AC1100 Baby Sound Monitor to find out.