Bluetooth Signal Strength: What You Can Really Check
Your phone almost certainly cannot show you Bluetooth signal strength. There is no such reading in iPhone Settings, and Android does not put one in Settings either.
The number people are chasing is called RSSI. It is a developer level measurement, not a bar graph waiting to be found.
There is a bigger problem with it, and almost nobody says this out loud. The tidy “good, fair, poor” RSSI charts you see all over the web are not from any official source, and the Bluetooth spec makes a single chart impossible.
So this guide does two things. It explains what the number really is, and then it skips to what actually works: fixing the connection.
What is Bluetooth signal strength?
RSSI stands for Received Signal Strength Indicator. It is the receiving device’s report of how strong the incoming radio signal is.
Here is where it falls apart as a simple score. The Bluetooth Core Specification defines RSSI two completely different ways depending on which kind of Bluetooth link you are on.
On classic Bluetooth (the kind your speaker and headphones use for audio), RSSI is not a signal level at all. It is an offset from a target range the controller picks, where zero means “inside the ideal range.”
Read that again, because it flips the usual advice. On classic Bluetooth, zero is good. It is not a terrible score.
The spec also says plainly that this value “is not required to have any specific accuracy.”
On Bluetooth Low Energy, RSSI is a real signal level in dBm. But the spec only requires it to be accurate to within 6 dB in either direction.
A 6 dB tolerance is wide. It is wide enough on its own to make a bucket like “minus 40 to minus 55 is strong” meaningless.
Why the RSSI charts you see online are wrong
Almost every page on this topic prints a table like “minus 40 to minus 55 is strong, minus 100 is unusable.” Our own old version of this article printed one, and it even contradicted itself.
No such table comes from the Bluetooth SIG, Apple, Google, or Microsoft. It is folk convention that got copied from site to site until it looked official.
The Bluetooth SIG does publish something real: the minimum sensitivity a receiver has to hit. That is the level where a link is expected to still work.
| Bluetooth radio type | Required receiver sensitivity |
|---|---|
| Classic (BR/EDR) | minus 70 dBm or better |
| LE 1M and LE 2M | minus 70 dBm or better |
| LE Coded (S=2) | minus 75 dBm or better |
| LE Coded (S=8) | minus 82 dBm or better |
Those are floors, not quality grades. The SIG also notes that real radios usually do much better, and cites an average of about minus 103 dBm for the LE Coded PHY at 125K, its slowest mode.
That single fact kills the popular claim that minus 100 means a dying connection. A link running at minus 103 dBm on that mode is working exactly as designed.
The honest takeaway: closer to zero means stronger, and that is as far as the number safely takes you. An RSSI reading is only worth comparing to itself, on the same device, over time.
Can you check Bluetooth signal strength on your phone or computer?
On no major consumer platform is there a documented, built in signal strength readout. Here is the real state of things.
| Device | Built in way to see it? | What you actually get |
|---|---|---|
| iPhone and iPad | No | Apple documents no RSSI display anywhere in iOS. It is available to app developers only. |
| Android | No | Nothing in Settings. RSSI is exposed to apps, not to you. |
| Windows 11 | No | Microsoft documents no signal indicator in the pairing screens. It is a developer only value. |
| Mac | Not officially | System Report has a Bluetooth section, but Apple never documents a signal reading there. |
A few popular tricks deserve a warning, because they get repeated constantly and they do not do what people claim.
The Android “Bluetooth HCI snoop log” in Developer options does not show you signal strength. It writes a packet capture file for engineers to open in Wireshark later.
On Windows, the Device Manager Details tab does not list a signal strength property for Bluetooth devices. The property people point to lives in a different system entirely and cannot appear there.
On Mac, holding Option and clicking the Bluetooth menu is widely repeated advice. Apple documents that trick for WiFi, not for Bluetooth, so treat it as unofficial.
If you want to see System Report anyway: click the Apple menu, choose About This Mac, click More Info, then open System Report and pick Bluetooth in the sidebar.
How far is Bluetooth supposed to reach?
The Bluetooth SIG’s own summary of range is honest and a little funny: “More than a kilometer. Less than a meter.”
It depends on the radio, the transmit power, the antenna, and what is in the way. Bluetooth runs on the 2.4 GHz band, and transmit power across devices spans from 0.01 mW all the way up to 100 mW.
Devices get sorted into power classes. Note that the spec defines these by power only, with no distances attached.
| BR/EDR power class | Maximum transmit power |
|---|---|
| Class 1 | Up to 100 mW (20 dBm) |
| Class 2 | Up to 2.5 mW (4 dBm) |
| Class 3 | Up to 1 mW (0 dBm) |
Bluetooth LE uses a different table, and it has a class the classic list does not. LE Class 1 runs from 100 mW down to 10 mW, Class 1.5 from 10 mW down to 2.5 mW, Class 2 from 2.5 mW down to 1 mW, and Class 3 from 1 mW down to 0.01 mW.
You will see “Class 1 reaches 320 feet, Class 3 reaches 3 feet” quoted everywhere. Those distances do not appear in the current spec or on the SIG’s range page, so we are not going to hand them to you as fact.
One counterintuitive detail from the spec: more power is not always better. Blasting a high power signal at a device sitting right next to you can saturate its receiver and drop the link.
What actually weakens a Bluetooth connection?
These are the factors the Bluetooth SIG actually names.
Distance. Signal fades as it travels. This is the boring one, and it is the main one.
What is in the way. The SIG lists walls, windows, glass, wood, metal, concrete, and even humidity and precipitation as attenuators.
Metal is the worst offender because it reflects and scatters the signal. A phone in a metal locker or a speaker behind a refrigerator is fighting physics.
Worth knowing: the SIG pushes back on the myth that Bluetooth cannot go through walls at all. Sheetrock barely slows it down. Concrete is a different story.
A crowded 2.4 GHz band. Bluetooth shares that band with WiFi and plenty of other gear.
Bluetooth hops between frequencies many times a second specifically to survive this. That is a real mitigation, not marketing.
Your body. Putting your phone in a back pocket while your speaker sits across the room means the signal has to pass through you. This one is an inference from how 2.4 GHz behaves, not an official SIG claim, but it matches what people notice.
Now the myth. You will read everywhere that a low battery weakens your Bluetooth signal.
We could not find a single manufacturer or the Bluetooth SIG confirming or denying it. Transmit power is a design choice, not something that sags as the battery drains on a well built device.
So we are not going to tell you it is true, and we are not going to call it a myth either. It is unproven, and anyone stating it flatly is guessing.
How to make a Bluetooth connection stronger
Since you cannot read the number, work the causes instead. Start at the top.
- Move closer and remove the wall. Get the phone and the speaker in the same room with a clear path. If the problem disappears, it was distance or an obstacle, and you are done.
- Take the phone out of your pocket. Set it on a table with nothing on top of it. Point the front of the speaker toward you.
- Get it off the metal. Move the speaker off a metal shelf, out of a cooler, and away from the refrigerator or a grill.
- Turn off other Bluetooth gear nearby. If a smartwatch, a second speaker, and a car are all fighting for the same phone, disconnect what you are not using.
- Restart both devices. Power the speaker off and back on. Then turn Bluetooth off and on in your phone’s Settings and wait five seconds before turning it back on.
- Pair them again from scratch. On iPhone, open Settings, tap Bluetooth, tap the blue letter i next to the device, then tap Forget This Device. Put the speaker back in pairing mode and connect again.
- Update the firmware. Many speakers and headphones only get fixes through the maker’s phone app. Open the app and check.
If the audio cuts out only when you walk a few feet away, that is a range and obstacle problem, and steps 1 through 3 are your fix. If it cuts out sitting still, it is more likely interference or a firmware bug, and steps 4 through 7 matter more.
If none of that worked
Test the speaker with a different phone. That one test splits the problem in half.
If the second phone holds a solid connection across the same room, your first phone or its pairing record is the issue. If both phones drop, the speaker is the issue and it is time to check the warranty.
Also try the speaker in a completely different room in a different part of the house. Some dropouts are one bad corner with a busy WiFi channel, not a broken device.
If cutting out is your main symptom, our guide on why a Megaboom keeps cutting out walks through the dropout causes in more depth, and most of it applies to any brand.
Frequently asked questions
Is there an app that shows Bluetooth signal strength?
Yes, developer and scanner apps can read RSSI because the operating systems expose it to apps even though they do not show it to you. Just remember what you learned above: the number has no official quality scale, and on classic Bluetooth it is not even a signal level.
What is a good RSSI number?
There is no official answer, and that is the honest response. Closer to zero is stronger, and a reading is only meaningful compared to other readings from the same device in the same setup.
Does Bluetooth 5 have better range than older versions?
It can, through a mode called LE Coded that trades speed for sensitivity. That mode drops the data rate but works at weaker signal levels, which stretches usable range.
On the “four times the range” figure: the SIG promoted it when Bluetooth 5 launched and still hosts that claim on its blog, crediting LE Coded. It then dropped the number from its current range guidance in favor of “it depends,” which tells you how much weight to give it.
Why does my speaker sound fine but keep skipping?
Skipping is usually interference or an obstacle rather than a weak overall signal. Move the phone into the open, put it in the same room, and turn off other Bluetooth devices you are not using.
Does a case block Bluetooth?
A normal plastic or silicone case will not meaningfully block it. A thick metal case, a metal pop socket, or a metal wallet attachment sits right on the antenna and can, so try without it if you are troubleshooting.
If your speaker connects but no sound comes out at all, that is a different problem, and our guide on a Bluetooth speaker that is connected but not playing is the right place to start. If it cuts out only while plugged in, see whether it is safe to use a Bluetooth speaker while charging.
Pairing trouble on Apple gear specifically is covered in our walkthrough on connecting Bluetooth headphones to an iPhone. And if range and durability are what you are really shopping for, our JBL versus Bose speaker verdict compares the two brands we get asked about most.