Main trade-off
Aqara Smart Lock B50
No fingerprint, Home Key or UWB.
Head-to-head
Aqara B50 vs U400: B50 uses AA batteries, U400 adds UWB with a rechargeable Thread setup
The short answer
B50 handles Wi-Fi app control and keypad entry with four AA batteries. U400 adds fingerprints, Home Key and supported-device UWB entry, with a rechargeable pack and Thread infrastructure.
Before you choose
The reasoning and the trade-offs
Hub-free can describe only one feature path
B50 is hub-free for its own Wi-Fi app, while U400's native Matter still needs home infrastructure.
What this is based on
B50 integrates Wi-Fi. U400 is a Thread endpoint that relies on a compatible controller and border router. Marketing labels cannot be compared without naming the desired feature.
Main trade-off
Aqara Smart Lock U400, Black
Thread infrastructure and UWB device checks add setup work.
Aqara Smart Lock B50
- Choose it for
- Remote guest codes and physical backup keys cover your needs.
- You want direct Wi-Fi control without a separate hub.
- Main trade-off
- No fingerprint, Home Key or UWB.
Aqara Smart Lock U400, Black
- Choose it for
- You want Home Key or fingerprints as daily entry methods.
- You have the compatible Apple devices and hubs for UWB entry.
- Main trade-off
- Thread infrastructure and UWB device checks add setup work.
About this comparison
Compare Aqara B50 and U400 for Wi-Fi guest codes, Home Key, hands-free UWB entry, fingerprint support and the home hubs each needs.
B50 handles Wi-Fi app control and keypad entry with four AA batteries. U400 adds fingerprints, Home Key and supported-device UWB entry, with a rechargeable pack and Thread infrastructure.
Winner by situation
Start with what you need it to do
Only keypad and remote app control matter
Both provide those functions with their required connection setup.
- Aqara Smart Lock B50
- Good
- Aqara Smart Lock U400, Black
- Good
Remote access with no Matter controller or Thread border router
B50 provides its own Wi-Fi connection. U400's connected Matter functions require compatible infrastructure.
- Aqara Smart Lock B50
- Better fit
- Aqara Smart Lock U400, Black
- Not suitable
Apple Home Key is mandatory
Only U400 supports Home Key.
- Aqara Smart Lock B50
- Not suitable
- Aqara Smart Lock U400, Black
- Better fit
Hands-free entry from an unspecified phone
B50 has no UWB. U400 requires a confirmed compatible device.
- Aqara Smart Lock B50
- Not suitable
- Aqara Smart Lock U400, Black
- Depends
What matters in practice
The differences that matter
Hub-free can describe only one feature path
B50 is hub-free for its own Wi-Fi app, while U400's native Matter still needs home infrastructure.
How we reached this conclusion
B50 integrates Wi-Fi. U400 is a Thread endpoint that relies on a compatible controller and border router. Marketing labels cannot be compared without naming the desired feature.
The expensive entry method may be unusable by a guest
UWB should be valued around enrolled, compatible-device users.
How we reached this conclusion
U400's hands-free access depends on specific hardware and setup. Occasional guests may still use the keypad on either lock.
A code-only household has less reason to step up
U400's extra hardware matters when someone uses Home Key, fingerprints or UWB.
How we reached this conclusion
Both provide keypad and physical-key access. The decision changes when an entry requirement goes beyond those shared methods.
Choice A
Aqara, DL-D12E
Smart Lock B50
A Wi-Fi keypad deadbolt for remote app control without an extra hub, with physical backup keys and optional Aqara Matter bridging.
- Best matched use
- remote guest access over home Wi-Fi
Checked facts
- Built-in 2.4 GHz Wi-Fi 6 provides remote Aqara Home app control.
- Four AA batteries have a manufacturer estimate of up to six months.
- The exterior is rated IPX3.
- Door thickness range is 35 to 54 mm, with 60 or 70 mm backset.
Choice B
Aqara, DL-D06E
Smart Lock U400, Black
A Matter-over-Thread deadbolt with fingerprint access, Apple home key and supported-device UWB approach unlocking.
- Best matched use
- A home with a suitable Thread controller and a compatible phone or watch
Checked facts
- The manufacturer lists fingerprint, keypad, mechanical key, NFC and supported wallet entry.
- The rechargeable battery can be charged through the interior USB-C port.
- The exterior panel is IP65 rated and the lock uses an internal gyro for door-close auto-lock.
- The selected Amazon model is DL-D06E, not a hub bundle.
Meaningful differences
What changes the fit
| What changes | Aqara Smart Lock B50 | Aqara Smart Lock U400, Black | Why it matters |
|---|---|---|---|
| Entry beyond codes | App and physical key | Fingerprint, Home Key and compatible UWB, plus app and key | U400 adds entry methods that cannot be installed on B50 through software. |
| Connected path | Built-in Wi-Fi 6 | Matter over Thread | B50 uses the existing Wi-Fi network. U400 depends on a suitable Thread and Matter setup. |
| Matter | Optional Aqara bridge | Native | B50's bridge requirement is separate from its hub-free app control. |
| Power | Four AA batteries | Rechargeable pack | Consider whether replacement cells or regular charging fits the household. |
| Exterior rating | IPX3 | IP65 | U400 documents dust protection and a higher water-test numeral. |
What you give up
Every choice has a cost
If you choose Aqara Smart Lock B50
- Matter requires a compatible Aqara bridge.
If you choose Aqara Smart Lock U400, Black
- A rechargeable pack needs a charging routine.
Recommendation switch
The decision flips if...
Home Key or fingerprints become mandatory
Choose Aqara Smart Lock U400, Black. U400 includes the relevant hardware.
The property will only have ordinary Wi-Fi
Choose Aqara Smart Lock B50. B50's direct Wi-Fi connection fits that installation.
The door fails both installation templates
Choose neither. A compatible mechanical fit is required before any entry feature matters.
What matters in practice
How to make the call
A property managed remotely
B50 is straightforward when remote codes and Wi-Fi are the goal. U400 is worth considering when daily occupants will use its more advanced entry methods and the property has compatible home infrastructure.
A mixed-device household
Check each person's phone and Watch rather than the most capable device in the house. Fingerprint and keypad fallback can matter more than the owner's UWB convenience.
Power and weather
B50 uses AA replacements and has the more limited published exterior rating. U400 requires charging its pack. Neither should be installed outside the manufacturer's environmental limits.
What this comparison cannot tell you
- The comparison uses published capabilities. It does not establish real-world unlock reliability or resistance to forced entry.
What the facts say
What the comparison shows
Useful conclusions from the current smart locks comparison, followed by the checked facts used to reach them.
Compared set
Only 1 of 25 models checked match every need here: “Control it away from home without a hub”, “Give family and guests a code”, “Unlock with a fingerprint”, and “Have the door unlock as I arrive”.
1 matching model from 25 checkedSee the checked facts and calculation notes
Match countThe count uses the current product-to-need assignments for “Control it away from home without a hub”, “Give family and guests a code”, “Unlock with a fingerprint”, and “Have the door unlock as I arrive”. A need with no documented match does not count.
| Product | Needs matched | Checked facts | Source records |
|---|---|---|---|
| Aqara Smart Lock B50 |
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| Aqara Smart Lock U400, Black |
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Ready to choose?
Check the price. Read the owner reviews.
Open either model on Amazon to check the current price, customer reviews and delivery options.
Aqara Smart Lock B50
Remote guest codes and physical backup keys cover your needs.
See price & reviews on AmazonAqara Smart Lock U400, Black
You want Home Key or fingerprints as daily entry methods.
See price & reviews on AmazonLinks open in a new tab.