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What we like
Set up took less than 5 minutes
What we don’t like
Batteries not included
Not very energy-efficient in battery mode
Range: 300 metres indoors | Two-way talk: No | Standby mode: Yes | Sound alerts: Yes | Motion alerts: No | App control: No | Power source: Battery or mains | Wifi: No
How we tested
Our parent-tester Eleri tested the monitor with her baby over the course of 6 weeks. She took careful notes on a number of factors, including ease of use, sound quality, reliability and design.
What’s the AM21 like to set up and use day-to-day?
The Motorola AM21 is an audio-only baby monitor that can run on batteries or be plugged into the mains. It took Eleri less than 5 minutes to get the monitor up and running.
With no complex extra features like video, two-way talk or an app to contend with, the AM21 is refreshingly straightforward to use. When your baby’s quiet, it automatically switches to power-saving eco mode, and switches back on as soon as your baby makes a sound.
The monitor has an unobtrusive green light which activates when a noise is detected. There’s a low battery alert and the microphone is really sensitive, offering parents peace of mind.
During testing, the monitor was dropped a couple of times - par for the course when you have little ones - and it showed absolutely no signs of damage. Its sturdy construction is built for real life and its simple, chunky controls mean not much can go wrong with it.
Some parents prefer a monitor that’ll give them information on their baby’s movements, breathing and allow them to check in via video at any time, and there are lots of monitors on the market with a wide variety of clever features - check out our round up of the best baby monitors to find out which ones Mumsnetters rate most highly. However, some think that these extra features can actually increase some parents’ anxiety levels, due to the ability to constantly check for updates. A simple, audio-only and screen-free device can be a godsend if you find yourself glued to the app or parental unit of a more high-tech monitor.
Eleri tested the monitor with her 8-month-old, and as an audio-only monitor we think it’s the best out there. It’s also great for toddlers, when you want to stay connected but no longer feel the need for a video monitor. At under £30, it’s also a great option for a second monitor, for taking on holiday or keeping at the grandparents’ house.
What’s the sound quality like?
As you’d expect from a budget baby monitor, the sound quality isn’t amazing, but it does the job and you can clearly hear when your baby makes a sound or cries.
A little tinny but it did its job - picked up every sound and I heard it clearly!
While most new parents opt for a video monitor these days, there’s a lot to be said for a no-frills, audio-only device like the AM21. Without alerts or displays for anything other than sound, it’ll only wake you when there’s a noise in your baby’s room like crying or babbling, plus there’s no screen to light up your bedroom in the middle of the night.
How reliable is the signal?
Using DECT technology, the parent and baby units stay connected without the need for WiFi, making it secure and reliable. Eleri couldn’t fault the signal strength, which didn’t let her down during the testing period at all.
We live in a small 2 bed terraced house so didn't push it’s limits, however the signal never cut out.
With both mains and battery power options, you’ve always got a backup if there’s a power cut or the batteries are flat. Speaking of which, we were disappointed to see that batteries aren’t included with the monitor, and Eleri found that when used in battery mode, they needed changing pretty frequently.
Is it good value for money?
At the time of writing, the Motorola AM21 is just £25, which is standard for an audio-only monitor. The VTech BM1000 is marginally cheaper, but we think the Motorola has the edge when it comes to signal strength and reliability. If you’re looking for a monitor that’ll do the job without breaking the bank, the AM21 is our top pick.
However, if you’re on a budget but decide you do want the benefits of a video monitor, the highly-rated VTech 3254 is just £50. All in all, the AM21 is a high quality audio monitor from a trusted brand, and at a great price.
About Mumsnet reviews
All Mumsnet product reviews are written by real people after weeks of research and testing. We work hard to provide honest and independent advice you can trust. Sometimes, we earn revenue through affiliate (click-to-buy) links in our articles. However, we never allow this to influence our coverage.
About the author
Poppy O'Neill is a Content Editor at Mumsnet and a mother of two. She's been researching and reviewing baby and child products for 2 years, with a particular focus on baby essentials, toys and books for toddlers and outdoor play equipment. From potties to paddling pools and bunk beds to bedtime stories, she loves to deep-dive into research and find the best products out there.
Poppy is also an award-winning, best-selling children's and parenting author of books such as Don't Worry, Be Happy, The Extraordinary Book That Makes You Feel Happy and Mother Power. She specialises in children's mental health and her books are used by therapists, teachers and SENCOs across the UK. She won a The Week Junior Book Award in 2023, her books have been translated into several languages and she's been featured in The Guardian, The Sunday Times and The Sun.
After earning a BA in Creative Writing from the University of Leeds and a PGCert in Fashion and Lifestyle Journalism from University of the Arts London, she worked in fashion for most of her 20s. When her children were young, she undertook an MA in Creative Writing from the University of Chichester and re-trained as an author and freelance writer.