“300 meters of range” sounds reassuring, but it only holds on open ground. Behind two concrete walls, 30 of those meters may survive. To compare range honestly, you first have to understand the technology behind the number: dedicated radio monitors transmit directly from unit to unit, while app-based monitors ride on your Wi-Fi or the internet. Those are entirely different rule books — and the reason one category thinks in meters while the other has no distance limit at all.
Three range worlds
From radio link to network path
Direct radio link (DECT/analog)
Baby unit and parent unit talk directly over radio. Range is a physical distance: typically 30–50 meters indoors, up to 300 meters outdoors.
Home Wi-Fi
Both devices talk to the router. “Range” now means your Wi-Fi coverage — no longer the distance between the two devices.
Internet
The devices connect across Wi-Fi and mobile networks. Distance stops mattering; the only question is whether both ends have stable network access.
What the meter figures of classic monitors actually mean
Makers of DECT baby monitors almost always quote two numbers: an outdoor range and an indoor range. A current DECT device such as the Alecto DBX120 states 50 meters indoors and 300 meters outdoors, for example. Those values are honest — but they are best-case values. The outdoor figure assumes a clear line of sight with not a single obstacle; the indoor figure assumes a few light walls at most.
Market comparisons put the open-field values even lower in places — some sources quote only 50 to 100 meters outdoors for digital DECT devices — but they all agree on the core point: indoors, 20 to 50 meters remain, depending on the building. Analog audio monitors reach 1000 meters and more on open ground, but share their frequencies with other devices and transmit unencrypted. Video monitors with their own radio usually sit around 50 meters. The order of magnitude is what matters: inside a house, the categories differ far less than the packaging suggests — in the end, the walls set the limit.
Three terms that make range claims readable
- Open-field range
- The distance with a clear line of sight and no obstacles. It is what the box quotes — and what a real home never delivers.
- Attenuation
- Every material between sender and receiver absorbs signal. Drywall costs little, reinforced concrete and underfloor heating cost a lot.
- Out-of-range warning
- DECT devices monitor their link continuously and alert you the moment the parent unit leaves the radio field — a real safety advantage over silently going quiet.
Walls are the real opponent
Whether radio monitor or Wi-Fi: both transmit in the low gigahertz range, where the same physics applies. Drywall costs little signal, solid brick more, reinforced concrete ceilings the most. Metal surfaces — large mirrors, refrigerators, coated windows — act as barriers, and microwaves or other radio devices add interference on top. That is why a “300-meter device” can fall silent two floors down in a terraced house while coping effortlessly across the garden.
The practical consequence: the biggest number on the box does not win — the setup that bridges your actual walls does. With a radio device, only a test in the real spot helps. With a Wi-Fi solution you have another lever: the router, whose position you control, or a repeater that carries coverage to where the nursery is.
| Technology | Typical range | What limits it |
|---|---|---|
| Analog (radio) | Up to 1000 m open field, far less indoors | Walls, interference from other radio devices, no encryption |
| DECT (radio) | 30–50 m indoors, up to 300 m open field | Walls and ceilings; in return an out-of-range alert and a low-interference channel |
| App on home Wi-Fi | As far as your Wi-Fi reaches | Router position, repeater coverage, network quality |
| App over the internet | No distance limit | Stable network access on both ends, battery, mobile coverage |
For app monitors, “range” is the wrong question
Once two smartphones take over the baby monitor roles, neither device transmits directly to the other anymore. Both talk to the router — and the distance between baby device and parent device becomes technically meaningless. Whether you are two rooms or two countries away changes nothing about the connection, as long as both devices have network access. The relevant questions shift: how well does your Wi-Fi cover the nursery? What happens when a device switches from Wi-Fi to mobile data? And does the app honestly show when the link is currently down?
Technically, standards like ICE make this work: they automatically negotiate the best path between two devices for WebRTC connections — direct where possible, via a relay where routers or foreign networks block the way. For parents this means no port forwarding, no static IP, no router surgery. What does deserve attention is the foundation itself: guidance such as the NCSC’s advice on smart devices in the home covers exactly the network hygiene every app-based solution builds on.
Which range technology fits your situation?
almost any technology will do — including a simple DECT device. Decide on handling, sound, and price, not on meters.
a solid Wi-Fi network with an app-based monitor beats any radio link — provided the coverage is good at the crib. A repeater is cheaper than a new baby monitor.
there is no way around an internet connection. Then pay special attention to encryption, secure pairing, and an honest connection status.
Getting the most range out of your setup
- Halve open-field figures (at least) whenever walls or ceilings sit in between.
- With a radio device: test the link at the actual sleeping spot, not in the shop — and trigger the out-of-range alert once on purpose.
- With an app monitor: check Wi-Fi reception right at the crib; if it is weak, move the router or add a repeater.
- Do not hide the router in the basement: placed centrally and elevated, it covers more floors.
- For the garden or trips, deliberately test the internet path once before you rely on it at night.
Frequently asked questions
How far does a classic DECT baby monitor really reach?
Indoors, 30 to 50 meters is realistic — less in buildings with heavy construction. The 300 meters from the datasheet apply only outdoors with a clear line of sight. In practice that means DECT works reliably inside a normal apartment, but across several reinforced-concrete ceilings or out into the garden it quickly runs out of signal.
Why is the actual range lower than the number on the box?
Because the packaging figure is an open-field measurement without obstacles. Inside a home, walls, ceilings, and metal surfaces attenuate the signal — reinforced concrete most of all. Other radio devices and microwaves interfere on top. Depending on the building, only a fraction of the advertised distance survives, often a third to a fifth.
How can I increase the range of my baby monitor?
For radio devices, position is the main lever: place sender and receiver as freely as possible, not behind cupboards or metal surfaces. For app-based monitors you extend range through your network — put the router centrally, or add a repeater near the nursery. For anything beyond the house, switching to an internet connection is the single most effective step.
Does a baby monitor app have more range than a dedicated monitor?
Inside the same Wi-Fi, its range equals your Wi-Fi coverage — usually more than any in-house radio link. Over the internet, the distance limit disappears entirely: the two devices can be arbitrarily far apart. In exchange, reliability now depends on network quality rather than meters.
Does an app baby monitor work in the garden or at the neighbours’?
Yes, in two ways: either your Wi-Fi reaches that far, or the parent device switches to mobile data and connects over the internet. The second path is the more robust one because it does not depend on Wi-Fi coverage at the property line. A short test before the first evening shows which path runs stably for you.
Sources and further reading
- Was bedeutet DECT beim Babyphone? · der-babyphone-test.de
- Alecto DBX120 DECT baby monitor (50 m indoors / 300 m outdoors) · Alecto Baby
- Reichweite von Babyphones: Audio, Video und WLAN im Vergleich · Babykare
- Babyphones im Test: Was taugen die Elternberuhiger? · Stiftung Warentest
- Smart devices: using them safely in your home · National Cyber Security Centre (UK)
- RFC 8445: Interactive Connectivity Establishment (ICE) · IETF
- Getting started with WebRTC · WebRTC
- Babyphone Timmy security and architecture · Babyphone Timmy