The catch
Aqara Smart Lock B50
Lacks fingerprint, Home Key and UWB.
Side by side
Aqara B50 vs U400: U400 adds UWB with a rechargeable Thread setup, and B50 uses AA batteries
Quick verdict
B50 gives you Wi-Fi app control and keypad entry on four AA batteries. U400 adds fingerprints, Home Key and supported-device UWB entry, plus a rechargeable pack and Thread infrastructure.
Before you buy
Why, and what it costs you
Only one feature path can be called hub-free
For its own Wi-Fi app, B50 is hub-free, but native Matter on U400 still needs home infrastructure.
Where this comes from
Wi-Fi is built into B50. U400 is a Thread endpoint, and it relies on a compatible controller and border router. Marketing labels can’t be compared until the desired feature is named.
The catch
Aqara Smart Lock U400, Black
Setup work grows with Thread infrastructure and UWB device checks.
Aqara Smart Lock B50
- Why pick it
- Your needs are met by remote guest codes and physical backup keys.
- Direct Wi-Fi control with no separate hub is what you want.
- The catch
- Lacks fingerprint, Home Key and UWB.
Aqara Smart Lock U400, Black
- Why pick it
- Home Key or fingerprints should be your daily way in.
- The compatible Apple devices and hubs for UWB entry are already yours.
- The catch
- Setup work grows with Thread infrastructure and UWB device checks.
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What this page compares
Aqara B50 and U400 are compared on Wi-Fi guest codes, Home Key, hands-free UWB entry, fingerprint support and the home hubs each requires.
B50 gives you Wi-Fi app control and keypad entry on four AA batteries. U400 adds fingerprints, Home Key and supported-device UWB entry, plus a rechargeable pack and Thread infrastructure.
Which one fits
Pick the situations that sound like you
Keypad and remote app control are all that matter
Those functions come with both, given the connection setup each requires.
- Aqara Smart Lock B50
- Good
- Aqara Smart Lock U400, Black
- Good
Remote access that needs neither a Matter controller nor a Thread border router
B50 brings its own Wi-Fi connection, whereas the connected Matter functions on U400 require compatible infrastructure.
- Aqara Smart Lock B50
- Better fit
- Aqara Smart Lock U400, Black
- Not suitable
Apple Home Key must be supported
U400 alone supports Home Key.
- Aqara Smart Lock B50
- Not suitable
- Aqara Smart Lock U400, Black
- Better fit
Hands-free entry using a phone that isn’t specified
UWB isn’t available on B50. U400 needs a device confirmed as compatible.
- Aqara Smart Lock B50
- Not suitable
- Aqara Smart Lock U400, Black
- Depends
In practice
Differences you will notice
Only one feature path can be called hub-free
For its own Wi-Fi app, B50 is hub-free, but native Matter on U400 still needs home infrastructure.
How we worked this out
Wi-Fi is built into B50. U400 is a Thread endpoint, and it relies on a compatible controller and border router. Marketing labels can’t be compared until the desired feature is named.
A guest may be unable to use the expensive entry method
Judge UWB by the enrolled users with compatible devices.
How we worked this out
Hands-free access on U400 depends on specific hardware and setup. Occasional guests may still use the keypad on either lock.
Less reason to step up exists for a code-only household
The extra hardware in U400 matters once someone uses Home Key, fingerprints or UWB.
How we worked this out
Keypad and physical-key access are on both. The decision shifts once an entry requirement goes past those shared methods.
Option A
Aqara, DL-D12E
Smart Lock B50
Remote app control works without an extra hub on this Wi-Fi keypad deadbolt, which also has physical backup keys and optional Aqara Matter bridging.
- Best for
- giving guests access remotely over home Wi-Fi
Facts we checked
- Remote control through the Aqara Home app comes from built-in 2.4 GHz Wi-Fi 6.
- The manufacturer's estimate for four AA batteries is up to six months.
- IPX3 is the exterior's rating.
- It covers doors 35 to 54 mm thick and a 60 or 70 mm backset.
Option B
Aqara, DL-D06E
Smart Lock U400, Black
Fingerprint access, Apple home key and UWB approach unlocking on supported devices come together in this Matter-over-Thread deadbolt.
- Best for
- A household with a suitable Thread controller plus a compatible phone or watch
Facts we checked
- Entry options the manufacturer lists are fingerprint, keypad, mechanical key, NFC and supported wallet.
- You charge the rechargeable battery through the interior USB-C port.
- An internal gyro handles door-close auto-lock, and the exterior panel is rated IP65.
- The Amazon model selected is the DL-D06E, rather than a hub bundle.
Spec by spec
Where they really differ
| Spec | Aqara Smart Lock B50 | Aqara Smart Lock U400, Black | In practice |
|---|---|---|---|
| Entry beyond codes | App and physical key | Fingerprint, Home Key and compatible UWB, plus app and key | Software can’t install on B50 the entry methods that U400 adds. |
| Connected path | Built-in Wi-Fi 6 | Matter over Thread | B50 runs on the Wi-Fi network already in place. U400 depends on a suitable Thread and Matter setup. |
| Matter | Optional Aqara bridge | Native | Hub-free app control on B50 is a separate matter from its bridge requirement. |
| Power | Four AA batteries | Rechargeable pack | Think about whether swapping cells or charging regularly suits the household. |
| Exterior rating | IPX3 | IP65 | Dust protection and a higher water-test numeral are documented for U400. |
Trade-offs
What each pick costs you
With Aqara Smart Lock B50
- A compatible Aqara bridge is required for Matter.
With Aqara Smart Lock U400, Black
- You need a charging routine for a rechargeable pack.
Change of plan
When the answer changes
Home Key or fingerprints are now required
Go with Aqara Smart Lock U400, Black. The relevant hardware comes with U400.
Ordinary Wi-Fi is all the property will have
Go with Aqara Smart Lock B50. That installation suits the direct Wi-Fi connection on B50.
The door doesn’t pass either installation template
Neither model fits. No entry feature matters until there is a compatible mechanical fit.
Decision guide
How to decide
B50 covers Wi-Fi app control and keypad entry with four AA batteries. U400 brings fingerprints, Home Key and supported-device UWB entry, together with a rechargeable pack and Thread infrastructure.
A property you run from afar
B50 keeps things straightforward when remote codes and Wi-Fi are the goal. A look at U400 is warranted when daily occupants will use its more advanced entry methods and the property has compatible home infrastructure.
A household with mixed devices
Check what each person's phone and Watch can do, not just the most capable device in the house. Fingerprint and keypad fallback can count for more than UWB convenience for the owner.
Batteries and weather
AA replacements power B50, which also has the more limited published exterior rating. U400 needs its pack charged. Do not install either lock outside the manufacturer's environmental limits.
What this page can’t tell you
- Published capabilities are the basis here, and they cannot show real-world unlock reliability or resistance to forced entry.
By the numbers
What the data shows
What we found across the smart locks we compare, plus the checked facts behind each finding.
How many fit
Only 1 of the 25 models checked meet every need here: “Run it remotely without needing a hub”, “Hand a code to family and guests”, “Use a fingerprint to unlock”, and “Walk up and let the door unlock itself”.
1 model fits, out of 25 checkedShow the facts and the math
How we countedThe count uses each product's current fit ratings for “Run it remotely without needing a hub”, “Hand a code to family and guests”, “Use a fingerprint to unlock”, and “Walk up and let the door unlock itself”. A need with no documented match is not counted.
| Product | Needs it meets | Facts we checked | Sources |
|---|---|---|---|
| Aqara Smart Lock B50 |
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| Aqara Smart Lock U400, Black |
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Ready to buy
See today’s price and what owners say
Open either model on Amazon for the current price, customer reviews and delivery options.
Aqara Smart Lock B50
Your needs are met by remote guest codes and physical backup keys.
See price & reviews on AmazonAqara Smart Lock U400, Black
Home Key or fingerprints should be your daily way in.
See price & reviews on AmazonEach link opens in a new tab.
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