Selecting the right Round Fingerprint Sensor Module is essential for achieving reliable biometric authentication while meeting your product's size, performance, and user capacity requirements.

     The CRM Series Fingerprint Sensor Modules are designed for a wide range of embedded applications, including smart door locks, access control systems, safes, lockers, attendance terminals, and other IoT devices. Although all four models share the same communication interface and command protocol, they differ in image resolution, sensor size, module dimensions, and fingerprint storage capacity.

     This guide compares the four Round Fingerprint Modules to help you choose the best solution for your application.

CRM Series Round Fingerprint Sensor Module Comparison Table

What Are the Differences Between CRM Series Round Fingerprint Sensor Modules?

1. Fingerprint Image Resolution

     The biggest difference among these Fingerprint Recognition Modules is the fingerprint image resolution.

         • CRM88L-20 / CRM88L-100: 88 × 88 pixels 

         • CRM120: 120 × 120 pixels 

         • CRM160: 160 × 160 pixels 

      Higher image resolution allows the Fingerprint Sensor Module to capture more fingerprint details, improving recognition accuracy and authentication reliability, especially in demanding applications.

      If your project requires the highest biometric performance, the CRM160 is the recommended High Resolution Fingerprint Module.

2. Fingerprint Storage Capacity

     The modules also differ in the number of fingerprint templates they can store.

         • CRM88L-20: Stores up to 20 fingerprints 

         • CRM88L-100: Stores up to 100 fingerprints 

         • CRM120: Stores up to 100 fingerprints 

         • CRM160: Stores up to 100 fingerprints 

      For personal devices or single-user products, CRM88L-20 is often sufficient. For commercial equipment or shared access systems, the remaining Round Fingerprint Sensor Modules provide greater storage capacity.

3. Sensor Size

      Sensor diameter directly affects the fingerprint sensing area and user experience.

     The larger 7.5 mm sensing area of the CRM160 makes fingerprint placement easier, making it an excellent Round Fingerprint Sensor Module for Smart Locks and access control systems.

4. Module Dimensions

      For embedded devices with limited installation space, module dimensions are an important consideration.

         • CRM120: 8.7 mm (smallest module) 

         • CRM88L-20: 10.5 mm 

         • CRM88L-100: 10.5 mm 

         • CRM160: 10.5 mm

     Thanks to its compact design, CRM120 is an ideal Compact Fingerprint Sensor Module for portable electronics, smart cabinets, and compact IoT devices.

5. Three-Color LED Ring

     Some Round Fingerprint Modules include an integrated three-color LED ring for visual status indication.

     The LED ring provides intuitive feedback during enrollment and verification, improving the overall user experience.

What Features Are Shared by All CRM Series Fingerprint Sensor Modules?

      Although each Round Fingerprint Sensor Module has different specifications, they all share several common features.

Same UART Communication Interface

      Every CRM module uses a 3.3V TTL UART interface, making it easy to integrate into embedded systems.

      As a standard UART Fingerprint Module, the CRM Series offers simple hardware connections and stable communication for microcontrollers such as STM32, ESP32, Arduino, and Raspberry Pi.

Same Communication Protocol

      All CRM Series modules use the same communication commands and software protocol.

      This allows developers to upgrade from one Embedded Fingerprint Module to another with minimal firmware modifications.

      Note: While the communication protocol is identical, fingerprint templates are generated differently. Therefore, fingerprint databases cannot be shared between different CRM models.

Which Round Fingerprint Sensor Module Should You Choose?

Choose CRM88L-20 if:

         • You need an economical Round Fingerprint Module 

         • Your application stores fewer than 20 fingerprints 

         • LED status indication is required 

Choose CRM88L-100 if:

         • You require storage for up to 100 users 

         • You want a reliable UART Fingerprint Sensor Module 

         • You need LED ring status indication

Choose CRM120 if:

         • PCB installation space is limited 

         • You need a Compact Fingerprint Sensor Module 

         • Higher image resolution is preferred 

         • LED indication is unnecessary

Choose CRM160 if:

         • You need the highest fingerprint recognition performance 

         • Your product benefits from a larger sensing area 

         • You are designing a premium Capacitive Fingerprint Sensor Module solution for smart locks or access control equipment 

Frequently Asked Questions

 Do all CRM Series Fingerprint Sensor Modules use the same interface?

    Yes. Every UART Fingerprint Module in the CRM Series communicates through a 3.3V TTL UART interface, making hardware integration consistent across all models.

 Can I replace one CRM Fingerprint Module with another?

   Yes. Since all modules share the same communication protocol, replacing one model with another is straightforward.

However, fingerprint templates cannot be transferred between different models, so users must re-enroll their fingerprints.

 Are fingerprint templates compatible between different models?

   No. Although every Round Fingerprint Sensor Module uses the same communication commands, each model generates different fingerprint templates. Existing fingerprint databases cannot be migrated between models.

 Which CRM model provides the best fingerprint recognition performance?

   The CRM160 Round Fingerprint Sensor Module offers the highest resolution (160 × 160 pixels) and the largest sensing area, making it the best choice for applications requiring maximum recognition accuracy.

Summary

   The CRM Series offers four Round Fingerprint Sensor Modules to satisfy different application requirements, from compact embedded devices to high-security biometric systems.

         • CRM88L-20 – Cost-effective solution for up to 20 users. 

         • CRM88L-100 – Increased storage capacity while maintaining the same compact design. 

         • CRM120 – Compact Embedded Fingerprint Module with higher resolution and the smallest footprint. 

         • CRM160 – Premium Capacitive Fingerprint Sensor Module featuring the highest image resolution, the largest sensing area, and an integrated LED ring.

   All CRM Series modules are UART Fingerprint Modules featuring a 3.3V TTL interface, identical communication protocols, and reliable biometric authentication performance. Whether you are developing smart locks, safes, attendance systems, access control devices, or IoT products, the CRM Series provides a dependable Round Fingerprint Sensor Module for a wide range of embedded applications.