USB was originally designed to have a host device (like a computer) and a peripheral device (like a mouse) with the host managing everything and also providing power. USB A to A doesn't work for host to host communication because both of them will be providing power, which will risk frying both of them. Be careful with that cord. Answer from Deleted User on reddit.com
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Amazon
amazon.com › Ruaeoda-USB-Cable-Male › dp › B07CDD45ZK
Amazon.com: Ruaeoda USB to USB Cable 1.5 ft, USB 3.0 Male to Male Type A to Type A Double Sided USB Cord for Data Transfer Compatible with Hard Drive, Laptop, DVD Player, TV, USB 3.0 Hub, Monitor and More : Electronics
Amazon.com: Ruaeoda USB to USB Cable 1.5 ft, USB 3.0 Male to Male Type A to Type A Double Sided USB Cord for Data Transfer Compatible with Hard Drive, Laptop, DVD Player, TV, USB 3.0 Hub, Monitor and More : Electronics
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Reddit
reddit.com › r/pcmasterrace › i have never seen a usb-a to usb-a before now.. why are they so uncommon?
r/pcmasterrace on Reddit: I have never seen a USB-A to USB-A before now.. Why are they so uncommon?
July 27, 2022 - What I meant for not using it for device to device is plugging in one computer to another computer, which would mean both were supplying power from each end. USB-A is only meant to be plugged into the “host” which would be a computer or a hub.
Discussions

cables - Why is USB Type-A to USB Type-A never used? - Electrical Engineering Stack Exchange
I was wondering why almost all USB cables that exist are USB-A to (Micro-USB | USB-C | USB-B | etc.) Why was USB-A to USB-A not a popular thing? Is there a technical reason this cannot work? More on electronics.stackexchange.com
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How to run OpenSUSE live from a USB? : openSUSE
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can i use a normal usb c cable to my pc for my quest 2? or do i need the link cable? : oculus
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USB A Connections to Newer Products
So the USB letters A, B, C only refer to the physical port. Adapters will inter convert with no problems. However, USB cables can transmit data and power using a wide range of protocols e.g. USB-2, displayport, thunderbolt. Electrically, there's no reason why an adapter wouldn't work, but it depends whether it can support the protocols and bandwidth required. In short, if your USB-A devices are simply for USB-1/2/3 data then they are compatible. Other types of data is more complex. More on reddit.com
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People also ask

What does a USB hub do?

A USB hub is a device that expands the number of USB ports available on a computer or other electronic device. It allows multiple USB devices to be connected to a single USB port on the host device. Essentially, a USB hub acts as a junction point, allowing users to connect various peripherals such as keyboards, mice, printers, external hard drives, and more to their computer or device. Many users look for the best USB hub to ensure reliability and compatibility. Here are some key functions and features of USB hubs:

1. Expansion of USB Ports: The primary function of a USB hub is to provide additional USB ports beyond what the host device offers. This allows users to connect multiple USB devices simultaneously.

2. Data Transfer: USB hubs facilitate data transfer between the connected devices and the host device. Data can be transferred at various speeds depending on the USB standard supported by the hub (e.g., USB 2.0, USB 3.0, USB 3.1, etc.).

3. Power Distribution: Some USB hubs also provide power to connected devices, particularly useful for devices that require power to operate, such as external hard drives or smartphones. These hubs often come with dedicated power adapters to supply sufficient power to all connected devices.

4. Plug-and-Play Convenience: USB hubs are typically plug-and-play devices, meaning they can be connected to the host device without requiring any additional software installation. Once connected, the host device should recognize the hub and any devices connected to it.

5. Portability: USB hubs come in various sizes and form factors, including compact and portable designs, making them convenient for use with laptops or other mobile devices that have limited built-in USB ports. Many users prefer a USB C Hub for modern laptops due to its versatility and compact design.

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us.ugreen.com
us.ugreen.com › collections › usb-hub
USB Hubs & Docking Stations | Multi-Port Solutions for Your Devices ...
Can a USB-C hub charge my laptop while also connecting to other peripherals?

Yes, many USB-C hubs are equipped with Power Delivery (PD) functionality, which allows them to charge your laptop while also connecting to other peripherals. However, it's important to check the specifications of the USB-C hub to ensure that it supports the power requirements of your laptop and provides sufficient power output for charging while also supporting data transfer to connected peripherals. Additionally, the power output of the USB-C hub may vary depending on the number and types of peripherals connected, so it's advisable to confirm compatibility and functionality before making a purchase.

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us.ugreen.com
us.ugreen.com › collections › usb-hub
USB Hubs & Docking Stations | Multi-Port Solutions for Your Devices ...
How do I determine if my devices are compatible with a USB-C hub?

Determining compatibility between your devices and a USB-C hub involves several steps:

1. Check Device Ports: Ensure that your devices have USB-C ports or are compatible with USB-C adapters. Devices with USB-A, Micro USB, or other types of ports will not directly connect to a USB-C hub without adapters.

2. Review Hub Specifications: Look at the specifications of the USB-C hub to see what devices it supports. Ensure it offers compatibility with your specific devices, including laptops, smartphones, tablets, or other peripherals.

3. Power Delivery (PD) Support: If your devices require power delivery (such as laptops or smartphones), verify that the USB-C hub supports PD and provides sufficient power output to charge your devices.

4. Data Transfer Speeds: Confirm that the USB-C hub supports the data transfer speeds needed for your devices. For example, if you plan to connect external SSDs or high-speed storage devices, ensure the hub supports USB 3.1 Gen 2 or higher for optimal performance.

5. Operating System Compatibility: Check if the USB-C hub is compatible with the operating systems of your devices, such as Windows, macOS, Linux, Android, or iOS.

6. Read Reviews and Recommendations: Look for user reviews or recommendations online from others who have used the USB-C hub with similar devices. Their experiences can provide insights into compatibility and performance.

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us.ugreen.com
us.ugreen.com › collections › usb-hub
USB Hubs & Docking Stations | Multi-Port Solutions for Your Devices ...
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Cables
cables.com › … › home › pc cables › usb data cables › usb 2.0 a-a male cables › 1ft usb 2.0 a-male to a-male cable
1FT USB 2.0 A-Male to A-Male Cable
1FT USB 2.0 A-Male to A-Male Cable
USB 2.0 Rated High Quality Factory Molded Connectors This cable is used to transfer data between PCs with limited applications Not intended to create a network between workstations.  Reduce clutter on your desk with less cable to waste. 12 inch length is perfect for tight areas
Price   $10.00
Price   $$
Call   631-617-5190
Address   120 Marcus Blvd, Deer Park NY 11729
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Computer Cable Store
computercablestore.com › adapters & couplers › usb adapters › usb adapters › usb 2.0 adapter - usb a male to usb b female - 5 pack
USB 2.0 Adapter - USB A Male to USB B Female - 5 Pack | Computer Cable Store
USB 2.0 Adapter - USB A Male to USB B Female - 5 Pack
Description · Networx® USB 2.0 Adapter - USB A Male to USB B Female's will provide you with the ability to convert a USB cable's gender and connector type. Take note that when using this adapter to combine multiple USB cables, make sure that you do not exceed the 16 foot recommended USB limit. In order to extend your cable further, try our USB Active Extension cables. · USB 2.0 Adapter / Gender Changer · Connectors: Male USB A to Female USB B · Designed to convert a Female USB A to a Female USB B or a Male USB B to a Male USB A · Quantity: 5 Pack
(4.9)
Price   $5.79
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Yealink
yealink.com › en › product-detail › usb-connect-management
USB Connect | Yealink
Live Demo Service Room Configurator Deployment Tools Room Device Calculator Headset Selector NEW Headset Compatible Center NEW ... Support Home Pre-Sale Service After-Sale Service Trust Center Resource Center Yealink Academy Policy Center ... Partners Online Reseller IP Phone Engineer Microsoft Solution Engineer Headset Solution Engineer Multicell Engineer ... Yealink USB Connect is available for the management of multiple Yealink USB devices, including headsets, speakerphones, and webcams.
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UGREEN US
us.ugreen.com › collections › usb-hub
USB Hubs & Docking Stations | Multi-Port Solutions for Your Devices | UGREEN US
It allows multiple USB devices to be connected to a single USB port on the host device. Essentially, a USB hub acts as a junction point, allowing users to connect various peripherals such as keyboards, mice, printers, external hard drives, and more to their computer or device.
Find elsewhere
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Office Depot
officedepot.com › home › electronics › networking & cables › cables › usb cables
Usb Cables - Office Depot
Eaton Tripp Lite Series USB 3.2 Gen 1 SuperSpeed Device Cable (A to B M/M)... ... C2G 2m (6.6ft) USB 2.0 Cable - USB Cable - USB-A Male to USB Mini-B Male - Black...
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Newnex
newnex.com › usb-connector-type-guide.php
USB Types and Connectors Guide | Newnex
The USB standard has evolved significantly since its introduction, offering faster data transfer speeds, greater power delivery, and broader compatibility across devices. This section breaks down the major USB versions, from USB 1.0 to USB4, helping you identify which USB type matches your performance needs and connector compatibility.
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FireTech Supplies
firetechsupplies.com › products › replacement-usb-a-cord
Replacement USB-A to USB-A Cord – FireTech Supplies
Replacement USB-A to USB-A Cord
Six foot black cord with USB-A to USB-A ends.  Two cords are needed for the OMNIcheck to work properly.
Price   $25.00
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KVMGalore
kvmgalore.com › shopping › usb-a-to-a-cables-c-1004.html
USB A-to-A Cables
USB 2.0 A-to-A male-male cables designed to connect a USB port on a PC or Mac to a USB A-connector on a USB device, providing transfer rates up to 480Mbps. These fully-rated USB cables provide transfer rates up to 480Mbps, depending on USB version, and easily attach to any USB device.
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Custom Cable Connection
customcableconnection.com › products › usb-2-0-type-a-male-to-female
USB 2.0 Type A Male to Type A Female Extension Cable – Custom Cable Connection
These 2.0 universal serial bus ... USB 2.0 A Male to A Female Extension cable This cable features a standard USB A Male connector on one end and an A Female connector on the other and is particularly useful for extending the ...
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Micro Center
microcenter.com › home › accessories › cables & adapters › peripheral cables
QVS USB 2.0 (Type A) Male to USB 2.0 (Type-A) Male Cable 6 ft. - Black - Micro Center
2 weeks ago - Get it now! This cable connects your computer to any USB device with Type-A female port. It is USB 2.0 certified, has PVC jacket and supports USB speed up to 480Mbps.
Price   $-$$
Address   3089 Nutley St, 22031, Fairfax
Top answer
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USB-A male to USB-A female is fine. They exist, and are relatively common. They work just fine as USB extension cables, provided the overall length is not too long. For longer distances, active cables exist that contain an internal repeater or USB hub to regenerate the signal. However, you may run in to power delivery issues due to voltage drop.

USB-A male to USB-A male is dangerous. It is also not compliant with the USB specification*. They also exist, though I am not really sure why. Perhaps because the USB-A connector is shorter than the USB-B connector, so chinese external hard drive enclosure vendors decided to use it because it was a half a cent cheaper than the proper connector. A USB-A male to USB-A male cable is similar to a line cord with a male plug on both ends. You should never, ever use one of these. There are several problems. First of all, USB does not allow two USB hosts to be connected to each other. The software stack does not support it. You cannot simply connect two computers to each other via USB and have them talk to each other without inserting some component in the middle, such as two back-to-back USB to Ethernet converters or similar. USB on-the-go is a slightly different story as a USB OTG device will switch roles between host and device. USB OTG also uses a different connector entirely, an A/B variant that accepts both A and B type connectors, which only exists in the smaller sizes.

But this is not what makes USB-A to USB-A cables dangerous. What makes them dangerous is that the USB cable provides power, and USB hosts are in general not designed to accept power coming in the wrong way. If you connect two computers together with a USB-A to USB-A cable, their 5V supplies are almost certainly not at the same voltage, so one of them will power the other one through the USB cable. This in and of itself is not really a major problem, provided the source has appropriate current limiting to prevent the cable heating up and starting a fire. The problem really comes when one of the devices is turned off. Now, you have an external 5V supply coming in to a powered-off device that isn't designed to handle it. This can damage components on the motherboard in one or both devices. Also, USB devices are in general designed to draw less than 500 mA, but whatever is hanging off of the 5V rail inside a host could draw orders of magnitude more than that.

USB-C is a different story as is specifically designed to have identical connectors on both ends. Not only that, it is explicitly designed to support charging a host device via a USB C connector. As a result, USB C devices have to be designed to handle this situation appropriately.

*except for some extremely rare cables that you will most likely never come across that don't connect the 5V power, which are effectively indistinguishable from non-compliant cables unless you pull out a multimeter.

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Because it's against the standard. The USB standard says that type A is for hosts, and type B is for devices.

In practical terms, a device with a type A connector is expected to provide power, so if you connect two of them together, they will attempt to power each other, leading most likely to Bad Things Happening. Type C gets around this by a negotiation mechanism.

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OSForensics
osforensics.com › tools › write-usb-images.html
Tools for OSForensics - ImageUSB - Write an image to multiple USB Flash Drives
ImageUSB is a free utility which lets you write an image concurrently to multiple USB Flash Drives. Capable of creating exact bit-level copies of USB Flash Drive (UFDs), ImageUSB is an extremely effective tool for the mass duplication of UFDs. ImageUSB also supports writing of an ISO file byte by byte directly to an USB drive (*).
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Google Store
store.google.com › product › usb_c_usb_a_2
Google USB-C to USB-A Cable - Google Store
With this handy cable, your USB-A devices can be used with the latest USB-C laptops, phones and more for charging and data transfer.
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Walmart
walmart.com › cell phones
Male to Male USB Cables
From $6.34Cmple - USB to USB Cable 6ft USB A to A Male to Male USB 2.0 Cable Data Transfer USB Cord for Laptop, PC, USB Hub, Hard Drive, Laptop Cooler - Black
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Eaton
tripplite.eaton.com › products › usb-connectivity-types-standards
USB: Port Types and Speeds Compared | Eaton
However, as new standards bring more speed, power and versatility to market, they also bring a complex assortment of features and capabilities to consider when deciding which cable or peripheral is right for your application. In the 1990s, office desktops were a tangled mess of serial, parallel and proprietary cables. Universal Serial Bus (USB) changed all of that, simplifying computer connectivity through a small, inexpensive interface: the USB Type-A (USB-A) port/connector.
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Anker
anker.com › home › blog center › cables › usb a vs usb c: the differences & benefits for users
USB A vs USB C: Differences in Connectivity Standards - Anker US
December 5, 2024 - USB-A, also known as "Type-A," is the classic, rectangular-shaped connector that most people are familiar with. The USB-A dimensions are approximately 12mm x 4.5mm, making it larger and less compact compared to newer connectors. USB-A ports are widely found in various devices such as computers, laptops, power banks, and other electronic gadgets..