Official USB Compliance Testing & Logo Certification Services

Obtain comprehensive testing from USB experts for peripherals, hosts, hubs, and chargers that complies with official standards of USB4®, USB 3.2, USB 2.0, and USB Power Delivery at GRL, an Independent Test Lab (ITL) authorized by USB-IF.

Working closely with the USB ecosystem is what enables GRL experts to offer comprehensive range of services that spans compliance, certification and debugging.

Eligible for USB test standards and product types  

The following USB standard tests are available for cables and connectors (A, C) , Hosts, Host Silicon, Embedded Hosts, Peripherals ( Devices ), Hubs, and Hub Silicon:

  • USB4 Electrical Compliance
  • USB 3.2 & 2.0 Electricals
  • USB 3.2 & 2.0 CV/Functional
  • USB 3.2 & 2.0 Interoperability 
  • USB 3.2 Link Layer
  • USB Training: Debugging & Consultancy

All tests and services cover the following power delivery products:

  • Sources
  • Sink
  • DRP
  • E-marker Cables 

Reach out below for any USB testing related queries.

USB test overview

How USB began

USB stands for Universal Serial Bus and first arrived on the market in 1996. Since then, it has become the most common transmission interface in common consumer technology products such as desktops, laptops, monitors, and various electronic products. With each iteration, USB has been able to keep up with market demand through gradual increase of transmission speed, which is why it continues to be the most widely used interface on the market today.


Who are the USB-IF?

The USB Implementers Forum (USB-IF) Association is a non-profit organization co-founded by Apple, HP Inc., Intel Corporation, Microsoft Corporation, Renesas Electronics, STMicroelectronics, Texas Instruments, and other companies that develop the USB specification. The Forum works to unify and expedite the certification process while upholding high standards and simultaneously promotes the interface to new and existing markets. For more information about USB-IF may be found on their official website.


What are the latest versions of the USB Specification?

The USB 4 Specification is the most updated USB standard as of May 2021. As for USB-PD, the newest USB Power Delivery Specification Revision 3.1 came out in July 2022.


Product types that can be certified under USB 

The following table outlines product categories that can be certified under USB:

Categorization table of products certified under USB

Description and examples of products that can be USB certified, arranged according to category

USB4® test specification overview

USB-IF officially announced the specifications of USB4 on September 3, 2019. With architecture built upon Thunderbolt™ protocol specification, USB4’s main updates surrounded the supplementation of existing USB 3.2 and USB 2.0 architectures to build a new generation of USB featuring a maximum transfer rate of 40Gbps (two times more than the 20Gbps of the original USB 3.2) that enables the transfer of multiple data bits and images at the same time.


What are the main differences between USB4 & USB 3.2?

  1. USB4 speeds can go up to 40Gbps, two times faster than its predecessor USB 3.2 Gen 2x2
  2. The USB4 Tunneling architecture packs USB3 / DisplayPort™ / PCI Express® on the same interface for transmission, and the bandwidth allocation of each protocol can be dynamically adjusted.
  3. USB4 can be compatible with the Thunderbolt 3 system. While Thunderbolt 3 devices can fit into USB 3.2 ports as both use the USB-C port type, the device will not work since different standards are required.
  4. USB4 supports Host to Host (host and host docking transmission signal), a feature that was previously unavailable in USB 3.2.

Historical comparison of USB updates from USB 3.0 to USB4_issue dates_speed_logo_port & cable

Source: USB-IF. USB speeds from USB 3.0 to USB4.


The features described above make it obvious that the logical structure of USB4 is very similar to the network structure. A fixed frame and physical layer are used to carry different protocol packets, which can contain data and image packets, and each packet is marked with an address to ensure accurate transmission. This design allows USB4 to replace the functionally limited USB Hosts and USB Devices for a more flexible point-to-point signal transmission method. Apart from increasing speed, this unique design also serves as a good base point for future improvements in transmission speed and functions.


USB4 product types and specifications for tunneling support


Table of USB4 specifications for tunneling support based on Host_Hub/Dock_Device


*Note that TBT3 Compatibility must support 10.3125G, but 20.625G is optional.


USB4 certification test items


USB4 certification test items_host_hub/dock_device_silicon_end-product


Breakdown of USB4 test items 



  1. For the full list of products that need to use USB-IF approved connectors and chips, please log on to the USB-IF members’ portal.. 
  2. Ensure that your product has passed the respective compliance tests for USB 2, USB 3.2, USB PD, and USB Type-C®. Click on the embedded link to find out more about USB Power Delivery.

USB & USB PD Certification Test Process

Step-by-step guide to the USB & USB PD certification test process

Flowchart of certification test process for USB and USB PD_failure_DUT_Debugging


Flowchart of certification test process for USB and USB PD. Note that all connectors on USB products must be certified by USB-IF.

Refer to the embedded link for details on the EPR Cable (240W) certification test process.

Step 1: Apply for online registration qualification

All brand companies must obtain a USB Vendor ID (VID), a website account password for product registration in order to be eligible for obtaining USB certification.

Application for Vendor ID can be made here.

Step 2: Application process for TID

Application for TID can be done on the official USB-IF website.

Only members will be able to login to the USB portal for registration.

Step 3: Test sample & product information

The following details must be provided before USB and USB PD certification tests can commence:

USB Certification test items & instruments used

USB Certification test items for general products

USB certification test items_host_hub_peripheral_compound device_embedded host

USB certification test items for host, hub, peripheral, compound device, and embedded host with examples

USB test instruments for general products

USB3.2 electrical test:

  • Keysight scope DSOV334A 33GHz
  • Keysight M8020A
  • Anritsu MP1800/MP1900
  • Tektronix DPO72004C 20 GHz

USB 2.0 electrical test:

  • Keysight scope MSOS254A 2.5GHz

Link layer test & LVS test:

  • LeCroy M310P

Battery charging 1.2 test:


Interoperability test & framework test:

  • Dell XPS8930

Type-C functional test:

  • LeCroy M310P
  • Ellisys EX350

USB Cable/Conn certification test overview

USB Cable/Conn certification test process


Flowchart of the USB Cable/Conn certification test process  _debugging_test inquiry

Flowchart of the USB Cable/Conn certification test process

USB Cable/Conn certification test items

USB Cable/Conn certification test items according to USB standards and test groups_USB 2.0 to USB4_A1 to B8

USB Cable/Conn certification test items according to USB standards and test groups


Do be mindful of the following:

  1. Tests for USB 2.0, USB 3.2, USB4®, cable, and connector tests in the A1 group are different.
  2. A certified USB PD 3.0 E-Marker IC (USB4) is required for full-featured USB-C Cable (USB4 Gen2/Gen3) tests.
  3. B8 high-frequency tests have been added under the full-featured USB-C Cable (USB4 Gen2/Gen3) category.


USB cable & USB cable silicon power delivery certification test items

USB cable and cable silicon power delivery test items by test groups_PD Merged Test_Functional Tests_QuadraMax

USB cable and cable silicon power delivery test items by test groups

USB Cable/Connector test instruments used

USB cable and connector test instruments according to mechanical, environmental, and electrical & SI categories

USB cable and connector test instruments according to mechanical, environmental, and electrical & SI categories

Disclaimer: USB4®, USB, USB-C®, USB Type-C®, and USB-IF are registered trademarks of USB Implementers Forum. All information provided on this page are for reference and should not be regarded as an official communication of the USB Implementers Forum (USB-IF), which can be found on their website.

USB Power Delivery 3.1 certification test items & instruments used

USB Power Delivery compliance test specification Rev 1.2 (PD Merged Test Specification)

USB-IF released the latest version of the test specification-PD Merged Test Specification on June 23, 2021, which combines the original three documents of PD 3.0 test file, PD 2.0 Communication Engine MOI, and PD 2.0 Deterministic MOI while enabling response to extended power. It also adds a new test item, the PD Merged Test Specification.

The PD Merged Test Specification differs from older versions of CTS rules in the selection of test instruments. For details, please see the table below (new and old test specifications). Note that all connectors on USB products need to be certified by USB-IF. 

USB Power Delivery certification test items_PD Merged Test Specification_New and Old

USB Power Delivery certification test items based on new and old PD Merged Test Specifications

USB Power Delivery specification revision 3.1

The USB Promoter Group released the latest USB PD 3.1 (USB Power Delivery Specification Revision 3.1) on May 26, 2021. The USB Type-C® specification has also been updated to version 2.1. The biggest feature of the new specification is to increase the charging power to 240W and support voltage output of up to 48V.

To achieve high voltage output and ultra-high charging power, products should support the Extended Power Range (Extended Power Range) specification in PD 3.1.

USB Power Delivery Specification of power supply wattage

USB-IF has clear power supply design specifications for certified products. The following table (compiled by GRL) has been compiled to outline power supply specifications in accordance with the latest USB PD 3.1.

Original GRL table detailing USB Power Delivery specifications according to power supply wattage

Original GRL table detailing USB Power Delivery specifications according to power supply wattage

Specification differences between PD 3.0 vs. PD 3.1

The PD 3.1 specification compiles the original PD 3.0 into the Standard Power Range (SPR). As such, the maximum power remains the same as the original 100W, while increasing the Extended Power Range (EPR).

Specification differences between USB Power Delivery 3.1 and 3.0

Specification differences between USB Power Delivery 3.1 and 3.0

Note the following specification details:

  1. For charging power levels of 240W, the charger, cable, and terminal equipment must all support EPR. In particular, cables must support up to 5A, 50V.
  2. 240W is the maximum charging power supported under Power Delivery.
  3. Three new fixed voltages have been added: 28V (above 100W), 36V (above 140W), and 48V (above 180W).
  4. Three sets of adjustable voltages have been added

The new USB PD architecture defines a more stringent power protocol to ensure that high-power products can be used safely while enabling greater maximum charging power. In addition, safety requirements for products with power ranges between 100-240W have also become more stringent. Do refer to your target region’s country legislation regarding safety regulations before sending products for import.

USB Power Delivery test instruments

◎ Represents USB-IF approved instrument
▲ Represents USB-IF approved instrument application

PD Merged Test Specification:

Type-C Functional Test:

Battery Charging 1.2 Compliance Test:


Source Power Test:

  • QuadraMAX

Interoperability Test:

  • Google Pixel 4 Phone
  • Samsung Galaxy S21
  • Google Pixelbook Go
  • MacBook Air M1
  • ASUS 4K Monitor

PD 3.0 Test:

USB Embedded Host and Shared Power

USB Embedded Host allows USB peripherals to communicate directly with one another in the absence of an intermediary PC. Instead, Embedded Hosts enable direct connections between On-the-Go (OTG) devices, safely opening up communication channels with selected USB peripherals while simultaneously preserving battery life through power saving features. The continuous refinement of Embedded Host alongside USB Specifications has allowed electronic products to operate faster and more efficiently.


What is the difference between Host and Embedded Host?

There are subtle but significant differences between Host and Embedded Host that engineers should note. Additional features found within USB Embedded Hosts include support for specific peripheral devices or device classes, support for transfer types required by supported devices, and relaxed power requirements. Furthermore, hub support is also optional for embedded hosts.

An Embedded Host determines the types of devices that it can support through a Target Peripheral List (TPL). Entries in the TPL may include the VID or PID of specific products, or classes, subclasses, and protocols of products. Devices can perform dual roles when they support both Embedded Host and USB device functionality via two receptacles. For example, a phone functions as a peripheral device when downloading pictures to a PC, but becomes an Embedded Host when transferring pictures to a printer.

Determining the role that is being played boils down to the cables that are attached. When cables are attached to Type-A receptacles, the role of host is assumed. On the flipside, the role of device is assumed when cables are attached to Type-B receptacles. In most cases, both Type-A and Type-B receptacles must both operate concurrently unless they are only accessible one at a time. The advantage of USB OTG devices lies in their ability to dynamically switch between Embedded Host and peripheral device roles without changing cables. Instead of the typical Type-A and Type-B receptacles, OTG devices use a singular micro-AB receptacle that allows for adjustments by cable orientation. 


Latest Shared Power Spec Updates

While Shared Power specifications are still in the developmental phase, OEMs who are looking to test this functionality within their products can already do so using the GRL-A1-EPR Analyzer. Assessing Shared Power functionality can allow manufacturers to gain first-movers advantage, as experts believe that automotive solutions surrounding this specification will rapidly surface over the next 3-5 years. Furthermore, testing speeds and capacities will only continue to increase. GRL’s test engineers are already setting the standard by integrating AI and AI-EPR into USB-IF PD interop and Shared Power interop suites, as well as testing power speeds of up to 240W.

Check out the GRL-A1-EPR Analyzer

FAQs on USB4

1. Are products required to pass Thunderbolt certification after becoming USB4 certified?

Only USB4 certification is required for  products that both support USB4 and are Thunderbolt compatible. . However, obtaining Thunderbolt certification is still necessary if a manufacturer wishes to use the  "Thunderbolt 3" logo on their product packaging.

2. Must USB4 certification be obtained before Thunderbolt 4 certification?

No. The order in which both certifications are obtained do not matter.

3. Must applications for USB4, TBT3, and TBT4 certification be submitted separately?

Logos of USB and Thunderbolt belong to USB-IF and Intel respectively. Applications must therefore be submitted to their respective organizations.

4. Is compliance with Thunderbolt 3 equivalent to compliance with USB4?

No. TBT3 only tests EV (electrical characteristics of the signal) and FV (compatibility), while USB4 tests for a wider range of items. Refer to the USB4 test items section for more details.

FAQs on USB membership & test process

1. How to become a USB member?

Registration for USB membership may be done on the official USB-IF website.

2. How can a USB Logo be used?

Companies must pass the relevant USB tests, received product TID, and sign a Trademark License Agreement with the USB-IF before they are allowed to use the USB Logo.

More details on USB Logo usage specifications and agreement clauses may be found here.

3. How do we know if a product has obtained a USB TID?

The full list of TID of certified products can be found in the Integrator List on USB-IF official website.

4. Can products be resold to other manufacturers once certification and TID have been received?

 If the following conditions are met, OEM Arrangements can be carried out and resold.

  • Buyer must become a member of the USB Association if they aren’t already
  • Buyer must sign the USB-IF Trademark License Agreement

For more details of this arrangement, refer to the USB compliance page for OEM agreements


5. What modifications are required if a Family Model exists?

QbS (Qualification by Similarity) can be applied for specific modifications. Register for QbS here and refer to the USB-IF website for details on the degree of modification.

6. How long is USB VID valid for?

The USB VID is valid for life, even after your USB membership expires.

FAQs for USB testing

1. Which USB Legacy Connector products can be certified?

Certifiable USB Legacy Connector products include:

USB standards service_test lab_USB 2.0 vs 3.2 comparison table

Table of USB Legacy Connector products that can be certified

2. Which USB Legacy Cable products can be certified?

Certifiable USB Legacy Cable products include:

Table of USB Legacy Cable products that can be certified

Table of USB Legacy Cable products that can be certified

Note that the data wire gauge association of Standard A to Micro B and Standard A to Standard B cable must be 28AWG.

3. Do length limits apply with USB Legacy Cable certification?

Table of length limits according to various USB standards

Length limits according to various USB standards

4. Which USB Type-C to Type-C cables can be certified?

Table of USB Type-C to Type-C cables that are eligible for certification

USB Type-C to Type-C cables that are eligible for certification


5. What USB Legacy to Type-C cable can be certified?

Table of USB Legacy to Type-C cables that are eligible for certification

USB Legacy to Type-C cables that are eligible for certification

6. What USB adapter can be certified?

Table of USB adapters that are eligible for certification according to plug and receptacle

USB adapters that are eligible for certification

Note that although 2.0 C to Micro B Adapter does not need to be wired, 3.2 C to Standard A Gen1 Adapter has to be.

7. Are there special cables and architecture types that can pass USB certification?

Yes, there are. It is possible for the following types of cables and architecture be USB certified:

  • Type-C cable with LED lights
  • Tilted Head Type-C cable
  • Flat wire/telephone wire

The list above is non-exhaustive. If you have any special cables or architecture that you would like to verify, reach out to us: 

8. Are there any special connectors or architecture that are ineligible for USB certification?

Yes. The following types of cables and architecture have already been determined to be ineligible for USB certification:

  • Standard A+ Type-C Double Connector
  • Apple charging cable

Once again, you may contact us if you have any doubts over whether your cable or architecture products qualifies for USB certification at:: 

9. What preparation methods are used for USB Embedded Host testing?

All products must enter test mode before they can be analyzed. The USB-IF recommended way to enter test mode can be referenced in the following screenshot:

Screenshot of USB-IF recommendations on entering test mode


Should your product require an alternative method to enter test mode, please submit that information to GRL before testing at any of our labs. 

10. Can Type-C connectors be certified?

Whether or not Type-C connectors can be USB certified depends on a range of factors, which vary depending on whether or not EMC pads exist within the connector product:

If there are EMC pads in the product:

  • There are shrapnel above and below the iron case
  • Shrapnel on one side, convex hull on the other
  • The top and bottom of the iron shell are convex hulls, and the distance between the convex hulls must be greater than the thickness of the plug iron shell
  • The top and bottom of the iron shell are convex hulls, and the distance between the convex hulls must be greater than the thickness of the plug iron shell

There is no EMC pad inside the product

  • There is no shrapnel above and below the iron case
  • Shrapnel on one side, convex hull on the other

Feel free to contact us at for clarification on special products that do not fit any of the above descriptions.