Yep, I probably have the same one. Insanely useful, and it is also crazy how much variance there is in cables. You can’t believe what the sellers claim, so many times they end up being less capable than claimed.
Would this tell me if a cable is close to the end of it's life? I like to travel light and I've had cables (mostly phone/pad power) go out on trips after working as expected when I packed.
I think you would need something that tracks relevant per cable metrics over time to see if it is degrading.
That one just says yes/no, but maybe yes/no starts to flicker around its end of life?
Nod - that's what I was thinking. I expect it's often the connectors that deteriorate so perhaps moving them around while plugged in would tell me. Seems like a useful tool to have around.
i've used a treedix tester like this. the edition with many led lights, not the one with a screen.
wiggle the cables around to see if and when any of the lights flicker, indicating a bad or broken connection. i've found a few bad cables that would intermittently fail.
> I'm using the hardware tester from $INSERT_NAME_HERE
Oh god not again... before everyone starts naming their favourite brand, here's a 265 comment HN thread[1] (from last week !) on why these cheap USB-cable "testers" are not worth anything.
TL;DR You need a six-figure wallet to seriously call anything a "hardware tester" for USB cables. User ChrisMarshallNY has a one-liner summary buried in that thread:
Think about it. You need to generate a precise, calibrated, 40GHz signal, transmit it, then precisely measure the returned signal for phase, amplitude, and waveform integrity -at that speed. Oscilloscopes and logic analyzers that run at that speed, are damn expensive.
If you only paid $40 for a black-box on your favourite online marketplace, then what you've got is definitively NOT a USB-cable tester.
OK sure your 6 figures thing or even that 20k thing are way better testers than the Treedix. But for my use case, i.e. verify what's actually in the cable (not blindly trusting the marker) the latter is sufficient and very ergonomic, and the "real" testers are overkill.
> verify what's actually in the cable (not blindly trusting the marker) the latter is sufficient
But as was repeated 101 times on that thread ....
All that those cheap $40 boxes are doing IS reading the marker.
Sadly you are kidding yourself if you think a $40 box off Amazon is doing any sort of "verification". Let alone in any sort of calibrated, reproducible sense free of random unknown variables.
Am I missing something? For practical use you only care if it carries a certain amount of packets per second without excessive retries, not whether it preserves the waveform exactly.
> For practical use you only care if it carries a certain amount of packets per second without excessive retries
The $40 black-boxes do two things:
1. Basic electrical continuity test
2. Read the marker chips (if present)
There is zero chance that a $40 black-box, even if it did a naïve packet pushing test, would deliver you reproducible results and introduces all sorts of other random variables.
"Excessive retries" sounds like exactly the sort of intermittent, hard-to-diagnose cable issues that you will not find unless you test the USB cable on a 6-figure rig. :)
Are you suggesting there is no middle ground and that simply knowing if a USB-C cable is a USB C cable or a fake one can't be done with a cheap tester?
Huh? Decent quality cable testers can be had for like $20,000. There's a difference between a general-purpose oscilloscope or logic analyzer and a purpose-built domain-specific appliance. I probably could've saved up for one in just a few months back when I had a job earlier this year.
> Decent quality cable testers can be had for like $20,000.
See the discusison linked to.
Trust me, my interest was piqued by that thread and I went down the rabbit warren with Mr Google and spent far too much time on the subject. I looked at the various manufacturers and the setups required.
TL;DR: To start with, you need fancy harness assemblies. Then you need to plug those harnesses into very, very expensive equipment.
You're not going to find anything for $20k. High-throughput USB-cable testing simply can't be done the same way copper CAT6 certification can with a 20k Fluke.
For those who want to play with Mr Google, some manufacturers from my notes: Wilder Technologies, Allion, Keysight, Tektronix, Teledyne LeCroy
The only wrinkles for me are that Macs apparently don't interrogate cables when they don't have to, i.e., when the power adapter supplies <= 60W (not sure if that's a USB-C protocol or an Apple implementation limitation) and that the website copy is full of GPT-isms, which makes me suspect that some of the output might be assumed instead of empirically validated as well.
I came here to ask the same thing. I did find a Linux tool with the same name and purpose but that seems to be an entirely different codebase: https://github.com/nedrichards/whatcable-linux
I have a handful of wireless keyboards that just absolutely refuse to negotiate for charging with certain cables at all, so I'm hoping this will help me at least figure out what those keyboards are looking for in terms of cable.
I'm curious if this also works for USB-A to USB-C. The use case: My Suburu has USB-A inputs and only allows wired Carplay. When I upgraded my iPhone and ditched Lightning, I had to try 6 different cables from my cable drawer to find one that supported data transfer.
I have so many cables I've accumulated over the years, I should either purge or at least categorize the functionality of each.
For cheap cables like USB-A to USB-C, I just throw away all cables that do not support data transfer. I don’t need the mental overhead of categorizing these cables. So any USB-A to USB-C cable in my cable drawer would work in this scenario. And CarPlay doesn’t even require USB 3.0; 2.0 is enough.
I used to use one for Android. It worked for about 6 weeks, then stopped working, then a few months later I tried it and it worked for about 6 weeks before stopping working again!
I literally spent more than an hour yesterday debugging issues with USB-C cables that I wasn't aware were charging only, and this shows up today... Better late than never, I suppose, and definitely worth my ten quid.
If you can afford it, I'd honestly throw these out. "Charging only" is not a spec-compliant thing in USB-C, and personally I wouldn't want to re-discover which devices do and don't support them every time I just want to quickly grab a cable.
What's less easy to replace are all these damn USB-C devices lacking the UFP-identifying circuitry that only work on USB-A chargers using A-to-C cables...
To be clear, they're not literally "charging only", AIUI they're spec-compliant cables with USB2.0 480Mbps and power delivery, and they're allowed to not have the four SuperSpeed wire pairs. They're still useful for low bandwidth devices (like charging my keyboard/mouse).
Incidentally — I spent an inordinate amount of time searching for USB3.2 cables on Amazon, and the vast majority of cables were actually just USB2.0 cables with PD support, and not actual Full-Featured cables.
Ah, I love these as they're generally much thinner/lighter/more flexible than USB-C 3 cables but still support at least 60W power delivery! Advertising them as USB 3 is a shame, though.
I was trying to figure out slow network speeds one day and I finally swapped an ethernet cable and got full speed.
It turns out some ethernet cables are missing wires - and capped at 100Mbps! Wait what? I didn't even know that was a thing. I don't know where I got the wire, but into the trash it goes.
I would recommend getting one of the small cable testers, like the one from Treedix. Gives you all sorts of information very quickly, including resistance levels and capabilities.
Something that keeps needing to be pointed out every thread this stuff appears on: What these tools report are not functionally different from just believing "what's on the packaging", despite the misleading marketing claims.
These tools read a chip called an "eMarker". These eMarkers are programmed to say whatever the manufacturer wants them to say - there's no requirement that the information be based in reality. Plenty of cables have eMarkers that claim "40Gbps" or whatever speeds, or support 240W PD...but absolutely cannot deliver either of those. And none of these consumer level software or hardware testers can actually test either of those claims. They can only take the cable's own claims at face value.
Resistance measurements can cursorily test claims of 240W but resistance changes with temperature which changes with current...so unless your tester puts 5 amps down the wire for 5 minutes and then tests resistance it's not a very good test. AFAIK none of the testers flow 5 amps through the cable.
Actual maximum data throughput is very hard to know. The only way to really "know" how much data can flow through a cable is with an expensive oscilloscope or cable tester. Because 80Gbps cables run at ~13GHz, at minimum you need a 26GHz scope (Nyquist–Shannon sampling theorem) or more practically a 52GHz scope. And it turns out it's really expensive to measure electrical signals 52 billion times per second. The necessary devices start at $15,000 (cable signal integrity tester) [0] on the very low end and only work for max 10Gbps USB 3.2 cables, or past $270,000 for 80Gbps USB4 cables (proper 60GHz oscilloscope) [1].
On the high end, each signal integrity test device can actually cost $1-2 million [2] where the base unit starts at $670,000 plus then spending additional money for hardware-accelerated analysis, specialized active probes, and the specific PAM-3 / USB4 compliance software packages.
> Actual maximum data throughput is very hard to know. The only way to really "know" how much data can flow through a cable is with an expensive oscilloscope or cable tester.
Couldn't you just do a data transfer test over the cable and check the error rate? At least in theory, the controller might not report enough I guess.
If you are just wanting "to use it", sure.
If you are building a cable for a specific purpose, or want to actually ensure that it will work, use test equipment.
So basically, it's cheap for them to defraud the consumer, and prohibitively expensive for the consumer to adequately protect themselves from it. The absolute state.
While I totally agree if you want to truly know the quality of the signal you need a very expensive box to actually measure the tiny deviations, if the question is "can this thing handle 80Gbit of data", can't you just get a couple of USB4 chips or whatever and have one send a pattern at that throughput and have the other try and receive and confirm that pattern? That would give you a basic "yes/no" kind of answer of "can it send XGbit?" I agree the processing capacity for such a thing at retail isn't likely to be $40, but probably a good bit less than >$15k. After all, you can get <$1,000 laptops that can do that pretty easily.
For example, I don't need to precisely measure exactly how messed up the signal is to know if the HDMI cable works or not at a given resolution. I'll see the TV have issues displaying a picture. Either the picture is there reliably or its not. I'm not trying to fine tune the cable, I'm just trying to see if it generally works or not.
As for testing power delivery, its not that electrically complicated to put a few amps through a wire for a few minutes. That said, the user must be aware if the cable isn't up to the standards that the chip states you could have some serious issues on your hands, but I guess better to find out on the tester at the workbench or desk than at your bedside.
I'm using the hardware tester from Treedix in which you have to plug both ends of the cable and which tests a lot of things, I'm quite fond of it.
I have a basket with a lot of USB-c cables and without the tester I can't remember (nor guess) which one does what.
Yep, I probably have the same one. Insanely useful, and it is also crazy how much variance there is in cables. You can’t believe what the sellers claim, so many times they end up being less capable than claimed.
Would this tell me if a cable is close to the end of it's life? I like to travel light and I've had cables (mostly phone/pad power) go out on trips after working as expected when I packed.
I think you would need something that tracks relevant per cable metrics over time to see if it is degrading. That one just says yes/no, but maybe yes/no starts to flicker around its end of life?
Looks like the paid/pro version does this.
> Cable history
> Add a cable, give it a name, and WhatCable records how it performs over time, with a verdict per cable.
Nod - that's what I was thinking. I expect it's often the connectors that deteriorate so perhaps moving them around while plugged in would tell me. Seems like a useful tool to have around.
i've used a treedix tester like this. the edition with many led lights, not the one with a screen.
wiggle the cables around to see if and when any of the lights flicker, indicating a bad or broken connection. i've found a few bad cables that would intermittently fail.
> I'm using the hardware tester from $INSERT_NAME_HERE
Oh god not again... before everyone starts naming their favourite brand, here's a 265 comment HN thread[1] (from last week !) on why these cheap USB-cable "testers" are not worth anything.
TL;DR You need a six-figure wallet to seriously call anything a "hardware tester" for USB cables. User ChrisMarshallNY has a one-liner summary buried in that thread:
If you only paid $40 for a black-box on your favourite online marketplace, then what you've got is definitively NOT a USB-cable tester.[1] https://news.ycombinator.com/item?id=49152255
OK sure your 6 figures thing or even that 20k thing are way better testers than the Treedix. But for my use case, i.e. verify what's actually in the cable (not blindly trusting the marker) the latter is sufficient and very ergonomic, and the "real" testers are overkill.
> verify what's actually in the cable (not blindly trusting the marker) the latter is sufficient
But as was repeated 101 times on that thread ....
All that those cheap $40 boxes are doing IS reading the marker.
Sadly you are kidding yourself if you think a $40 box off Amazon is doing any sort of "verification". Let alone in any sort of calibrated, reproducible sense free of random unknown variables.
Am I missing something? For practical use you only care if it carries a certain amount of packets per second without excessive retries, not whether it preserves the waveform exactly.
> For practical use you only care if it carries a certain amount of packets per second without excessive retries
The $40 black-boxes do two things:
There is zero chance that a $40 black-box, even if it did a naïve packet pushing test, would deliver you reproducible results and introduces all sorts of other random variables."Excessive retries" sounds like exactly the sort of intermittent, hard-to-diagnose cable issues that you will not find unless you test the USB cable on a 6-figure rig. :)
Are you suggesting there is no middle ground and that simply knowing if a USB-C cable is a USB C cable or a fake one can't be done with a cheap tester?
> Are you suggesting there is no middle ground
Sadly yes.
Like many people on that thread concluded:
The best "middle ground" thing you can do is pay a premium to buy your cables from reputable manufacturers.
Huh? Decent quality cable testers can be had for like $20,000. There's a difference between a general-purpose oscilloscope or logic analyzer and a purpose-built domain-specific appliance. I probably could've saved up for one in just a few months back when I had a job earlier this year.
> Decent quality cable testers can be had for like $20,000.
See the discusison linked to.
Trust me, my interest was piqued by that thread and I went down the rabbit warren with Mr Google and spent far too much time on the subject. I looked at the various manufacturers and the setups required.
TL;DR: To start with, you need fancy harness assemblies. Then you need to plug those harnesses into very, very expensive equipment.
You're not going to find anything for $20k. High-throughput USB-cable testing simply can't be done the same way copper CAT6 certification can with a 20k Fluke.
For those who want to play with Mr Google, some manufacturers from my notes: Wilder Technologies, Allion, Keysight, Tektronix, Teledyne LeCroy
Here's one blog post I uncovered during my researches: https://www.keysight.com/blogs/en/tech/bench/2023/02/17/powe...
Aren't you both agreeing.. that it is way beyond $40? :)
You need a six figure wallet to want to spend $20k on a tester :)
> You need a six figure wallet to want to spend $20k on a tester :)
Heh. I'll give you a +1 for that one.
Reminded me of the old joke...
What's the quickest way to become a millionaire ? Be a billionaire and buy an airline.
Nice. You just got them a sale from me. I have a crap ton of cables so this will come in handy.
Exactly my use case.
And I have nothing to gain from that sale.
What would be really interesting is if I could connect a cable to two ports on a Mac and have the Mac test the cable.
> What would be really interesting is if I could connect a cable to two ports on a Mac and have the Mac test the cable.
Not reproducible and introduces all sorts of other random variables to your test (buffering etc.).
Great utility.
The only wrinkles for me are that Macs apparently don't interrogate cables when they don't have to, i.e., when the power adapter supplies <= 60W (not sure if that's a USB-C protocol or an Apple implementation limitation) and that the website copy is full of GPT-isms, which makes me suspect that some of the output might be assumed instead of empirically validated as well.
Is there something like this for Windows/Linux?
ChromeOS firmware has a bunch of this built in - it's super cool. https://nelsonslog.wordpress.com/2026/01/05/chromebooks-iden... and https://www.reddit.com/r/UsbCHardware/comments/1pyojjd/comme... and https://chromium.googlesource.com/chromiumos/platform2/+/HEA... is where I found out about it. A lot of the clever capabilities rely on the firmware that you have. Source - having spent a while a few weeks back getting Codex to poke at this topic on my machine https://github.com/nedrichards/whatcable-linux/blob/main/doc... since framework do reuse parts of the ChromeOS Embedded Controller in their firmware.
"This is a Linux-native reimplementation inspired by darrylmorley/whatcable"
https://github.com/nedrichards/whatcable-linux
But (hazard guess) it comes with a headless CLI binary (no GUI libraries needed) so probably could be ported to Linux (easily with an LLM?)
https://github.com/darrylmorley/whatcable
There is also https://github.com/Zetaphor/whatcable-linux (if you want a KDE UI rather than Gnome) and https://github.com/vzaliva/whatcable-linux-cli (a fork of the KDE repo, but only leaves the CLI tool).
WhatKable was right there!
There are options on Linux that you can google up (I don't know enough about any of them to endorse them by linking to one in particular).
As I understand it, Windows doesn't expose the necessary low-level hardware information for something like this to be possible.
A quick search found https://github.com/nedrichards/whatcable-linux, haven't tried it myself though
I came here to ask the same thing. I did find a Linux tool with the same name and purpose but that seems to be an entirely different codebase: https://github.com/nedrichards/whatcable-linux
I have a handful of wireless keyboards that just absolutely refuse to negotiate for charging with certain cables at all, so I'm hoping this will help me at least figure out what those keyboards are looking for in terms of cable.
I'm curious if this also works for USB-A to USB-C. The use case: My Suburu has USB-A inputs and only allows wired Carplay. When I upgraded my iPhone and ditched Lightning, I had to try 6 different cables from my cable drawer to find one that supported data transfer.
I have so many cables I've accumulated over the years, I should either purge or at least categorize the functionality of each.
For cheap cables like USB-A to USB-C, I just throw away all cables that do not support data transfer. I don’t need the mental overhead of categorizing these cables. So any USB-A to USB-C cable in my cable drawer would work in this scenario. And CarPlay doesn’t even require USB 3.0; 2.0 is enough.
This adapter works with my Android phone and makes my Android Auto wireless: https://aliexpress.com/item/1005008214786824.html
But it is the second product I tried; the first one didn't work (it's a 2020 Stellantis car). So, YMMV.
I'd recommend a wireless CarPlay adapter. I bought one for my car, and it's a game-changer.
I used to use one for Android. It worked for about 6 weeks, then stopped working, then a few months later I tried it and it worked for about 6 weeks before stopping working again!
I see other folks provided options, in case you want to avoid aliexpress, this one worked for me for the past 4 years
https://a.co/d/0d9EOGRW
Does require a bit of setup, can scan reviews to see if people have optimized a config for your specific vehicle
I literally spent more than an hour yesterday debugging issues with USB-C cables that I wasn't aware were charging only, and this shows up today... Better late than never, I suppose, and definitely worth my ten quid.
If you can afford it, I'd honestly throw these out. "Charging only" is not a spec-compliant thing in USB-C, and personally I wouldn't want to re-discover which devices do and don't support them every time I just want to quickly grab a cable.
What's less easy to replace are all these damn USB-C devices lacking the UFP-identifying circuitry that only work on USB-A chargers using A-to-C cables...
To be clear, they're not literally "charging only", AIUI they're spec-compliant cables with USB2.0 480Mbps and power delivery, and they're allowed to not have the four SuperSpeed wire pairs. They're still useful for low bandwidth devices (like charging my keyboard/mouse).
Incidentally — I spent an inordinate amount of time searching for USB3.2 cables on Amazon, and the vast majority of cables were actually just USB2.0 cables with PD support, and not actual Full-Featured cables.
Ah, I love these as they're generally much thinner/lighter/more flexible than USB-C 3 cables but still support at least 60W power delivery! Advertising them as USB 3 is a shame, though.
I was trying to figure out slow network speeds one day and I finally swapped an ethernet cable and got full speed.
It turns out some ethernet cables are missing wires - and capped at 100Mbps! Wait what? I didn't even know that was a thing. I don't know where I got the wire, but into the trash it goes.
100 Mbps is sometimes just enough for the job. And it’s easy to see that you only have two pairs instead of four – just look at the connector.
I would recommend getting one of the small cable testers, like the one from Treedix. Gives you all sorts of information very quickly, including resistance levels and capabilities.
Something that keeps needing to be pointed out every thread this stuff appears on: What these tools report are not functionally different from just believing "what's on the packaging", despite the misleading marketing claims.
These tools read a chip called an "eMarker". These eMarkers are programmed to say whatever the manufacturer wants them to say - there's no requirement that the information be based in reality. Plenty of cables have eMarkers that claim "40Gbps" or whatever speeds, or support 240W PD...but absolutely cannot deliver either of those. And none of these consumer level software or hardware testers can actually test either of those claims. They can only take the cable's own claims at face value.
Resistance measurements can cursorily test claims of 240W but resistance changes with temperature which changes with current...so unless your tester puts 5 amps down the wire for 5 minutes and then tests resistance it's not a very good test. AFAIK none of the testers flow 5 amps through the cable.
Actual maximum data throughput is very hard to know. The only way to really "know" how much data can flow through a cable is with an expensive oscilloscope or cable tester. Because 80Gbps cables run at ~13GHz, at minimum you need a 26GHz scope (Nyquist–Shannon sampling theorem) or more practically a 52GHz scope. And it turns out it's really expensive to measure electrical signals 52 billion times per second. The necessary devices start at $15,000 (cable signal integrity tester) [0] on the very low end and only work for max 10Gbps USB 3.2 cables, or past $270,000 for 80Gbps USB4 cables (proper 60GHz oscilloscope) [1].
On the high end, each signal integrity test device can actually cost $1-2 million [2] where the base unit starts at $670,000 plus then spending additional money for hardware-accelerated analysis, specialized active probes, and the specific PAM-3 / USB4 compliance software packages.
0: https://www.totalphase.com/products/advanced-cable-tester-v2...
1: https://www.edn.com/12-bit-oscilloscope-operates-up-to-65-gh...
2: https://www.eevblog.com/forum/testgear/uxr1104a-infiniium-ux...
> Actual maximum data throughput is very hard to know. The only way to really "know" how much data can flow through a cable is with an expensive oscilloscope or cable tester.
Couldn't you just do a data transfer test over the cable and check the error rate? At least in theory, the controller might not report enough I guess.
If you are just wanting "to use it", sure. If you are building a cable for a specific purpose, or want to actually ensure that it will work, use test equipment.
IT interconnect closet vs. air vehicle.
So basically, it's cheap for them to defraud the consumer, and prohibitively expensive for the consumer to adequately protect themselves from it. The absolute state.
While I totally agree if you want to truly know the quality of the signal you need a very expensive box to actually measure the tiny deviations, if the question is "can this thing handle 80Gbit of data", can't you just get a couple of USB4 chips or whatever and have one send a pattern at that throughput and have the other try and receive and confirm that pattern? That would give you a basic "yes/no" kind of answer of "can it send XGbit?" I agree the processing capacity for such a thing at retail isn't likely to be $40, but probably a good bit less than >$15k. After all, you can get <$1,000 laptops that can do that pretty easily.
For example, I don't need to precisely measure exactly how messed up the signal is to know if the HDMI cable works or not at a given resolution. I'll see the TV have issues displaying a picture. Either the picture is there reliably or its not. I'm not trying to fine tune the cable, I'm just trying to see if it generally works or not.
As for testing power delivery, its not that electrically complicated to put a few amps through a wire for a few minutes. That said, the user must be aware if the cable isn't up to the standards that the chip states you could have some serious issues on your hands, but I guess better to find out on the tester at the workbench or desk than at your bedside.
Small question: did anybody succeed to pay via Apple Pay?
Give me the freakin bit error rate please.