Best Real Time Clocks of 2026

Harvey Wall Avatar
Harvey Wall
Last Updated: 2 Feb 2026

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Real Time Clocks (RTC) are electronic devices that keep track of time even when the power is off. They are commonly used in electronic devices such as computers, mobile phones, and digital cameras. These clocks are accurate and reliable, and can be used to timestamp events, schedule tasks, and trigger actions. RTCs are available in various sizes and configurations, and can be easily integrated into electronic circuits. They are a must-have component for any electronic device that requires accurate timekeeping.

At a Glance: Our Top Picks

APKLVSR Real Time Clock Module with Battery Cover #TOP 1
APKLVSR Real Time Clock Module with Battery
ftb score rating icon 9.8
DS3231 High Precision RTC Module for Arduino Cover #TOP 2
DS3231 High Precision RTC Module for Arduino
ftb score rating icon 9.7
DollaTek DS1307 Real Time Clock Module Cover #TOP 3
DollaTek DS1307 Real Time Clock Module
ftb score rating icon 9.5

Top 8 Real Time Clocks

#TOP 1

APKLVSR Real Time Clock Module with Battery

AT24C32
APKLVSR Real Time Clock Module with Battery Cover
APKLVSR Real Time Clock Module RTC Sensor, AT24C32 IIC Precision Clock With Battery, I2C Compatible With Arduino

The APKLVSR RTC Module is an affordable and precise I2C real-time clock that features an integrated temperature-compensated crystal oscillator. You can set two alarms, ensuring you never miss an important event. It also monitors the power supply to detect outages, providing a reset output for added safety. Additionally, the module keeps track of the full calendar, including leap years, making it easy for you to stay organised and on schedule.

What We Like
Highly accurate timekeeping
Power outage detection
Automatic date adjustments
Two programmable alarms
#TOP 2

DS3231 High Precision RTC Module for Arduino

DS3231
DS3231 High Precision RTC Module for Arduino Cover
2pcs DS3231 High Precision RTC Real Time Clock Module 3.3V/5V for Arduino Raspberry Pi

The DS3231 RTC Module is an advanced real-time clock designed for both 3.3V and 5V systems. With outputs of 1 Hz and 32.768 kHz, it provides precise timing for various applications. You'll appreciate its high accuracy, featuring a built-in digital temperature sensor with a precision of ±3℃. Additionally, the module operates within a wide temperature range of -40 °C to +85 °C, ensuring reliable performance in diverse environments. This makes it an excellent choice for projects requiring dependable timekeeping and temperature monitoring.

What We Like
High precision timekeeping
Wide temperature range
Sturdy and durable design
Compatible with various systems
#TOP 3

DollaTek DS1307 Real Time Clock Module

DollaTek
DollaTek DS1307 Real Time Clock Module Cover
DollaTek Tiny RTC I2C DS1307 AT24C32 Real Time Clock Module For Arduino AVR PIC 51 ARM

The DollaTek DS1307 Clock is an efficient real-time clock module designed for various applications. It features a low power consumption design, ensuring that you can keep accurate time without draining your resources. With its 32K I2C EEPROM memory, you can easily store and retrieve important data, adding convenience to your projects. The clock pin provides a seamless clock signal for connected microcontrollers, facilitating smooth integration within your systems. Additionally, this module supports cascading of other I2C devices, enhancing the overall functionality of your setup.

What We Like
Low power consumption
Data storage and retrieval
Seamless microcontroller integration
Cascading I2C devices
#TOP 4

DAOKAI DS1307 I2C Real Time Clock Module

WE-DA-064
DAOKAI DS1307 I2C Real Time Clock Module Cover
DAOKAI 5PCS Tiny RTC I2C Real Time Clock Module AT24C32 Storage Memory High Precision DS1307 Clock Module for Arduino for AVR ARM PIC SMD, with Straight Single Row

The DAOKAI RTC Module is a versatile real-time clock featuring the DS1307 I2C chip and a 32K EEPROM memory. It conveniently counts seconds, minutes, hours, days, and even months, ensuring accurate timekeeping. With a rechargeable lithium battery and charging circuit, it can maintain functionality for up to one year when fully charged, although the battery is not included. Additionally, it offers low power consumption and automatic brownout detection, making it an ideal choice for various projects.

What We Like
High precision timekeeping
Rechargeable battery support
Low power consumption
Leap year compensation
Cascadable with other I2C devices
#TOP 5

DollaTek 3Pcs Real Time Clock Module for Arduino

DollaTek 3Pcs Real Time Clock Module for Arduino Cover
DollaTek 3Pcs Tiny AT24C32 I2C Module Precision Real Time Clock Module For Arduino

The DollaTek RTC Module is a cost-effective and precise I2C real-time clock designed for Arduino projects. It features an integrated temperature-compensated crystal oscillator for improved long-term accuracy, ensuring that you can rely on the timekeeping capabilities. With a battery input, this module continues to function even without main power, giving you peace of mind about maintaining accurate time. Additionally, its compact design reduces the number of components needed, streamlining your production process. This module is ideal for anyone needing reliable time management in their projects.

What We Like
Highly accurate timekeeping
Battery backup for reliability
Compact and easy to use
Reduces component count
#TOP 6

DS3231 High Precision Real Time Clock Module

fasient1
DS3231 High Precision Real Time Clock Module Cover
fasient1 DS3231 High Precision Clock Module DIY RTC Board Real Time Clock Memory Module for,Low Power Consumption

The DS3231 Clock Module offers exceptional features for accurate timekeeping. With its dual calendar clock, you can easily keep track of time, even during power outages, thanks to the continuous timing battery backup. This module is compatible with the DS3231 encapsulation and function, ensuring seamless integration into your projects. It also provides comprehensive calendar functionalities, including seconds, minutes, hours, days, months, and years, all the way until the year 2100. This reliability makes it a perfect choice for various applications.

What We Like
Accurate timekeeping
Battery backup feature
Comprehensive calendar functions
Low power consumption
#TOP 7

DollaTek 10Pcs DS1307 Real Time Clock Module

Tiny RTC DS1307
Blue
DollaTek 10Pcs DS1307 Real Time Clock Module Cover
DollaTek 10Pcs Tiny RTC I2C DS1307 AT24C32 Real Time Clock Module For Arduino AVR PIC 51 ARM

The DollaTek RTC Module features a DS1307 I2C real-time clock chip combined with a 24C32 32K I2C EEPROM memory. This fully assembled module includes a CR2032 battery, making it ready for use right out of the box. It is designed specifically for compatibility with Arduino, ensuring you can easily integrate it into your projects. As a substitute accessory, it provides a reliable solution for accurate timekeeping in your electronic applications.

What We Like
Fully assembled for convenience
Includes CR2032 battery
Compatible with Arduino
Reliable timekeeping
Easy integration into projects
#TOP 8

Socobeta DS3231 RTC Real Time Clock Module

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Socobeta DS3231 RTC Real Time Clock Module Cover
Socobeta RTC Clock Module DS3231 RTC Board Real Time Clock Module for

The Socobeta DS3231 RTC Module is a highly precise clock designed to keep accurate time, including seconds, minutes, hours, days, dates, months, and years, even accounting for leap years until 2100. This module is adaptable to both 3.3V and 5V systems, making it easy to integrate without additional level conversion. Its low power consumption ensures efficient operation, and the continuous battery backup means you won’t lose time data during power outages. Additionally, the module is made from high-quality materials, offering better accuracy and a reliable fit for your equipment.

What We Like
High precision timekeeping
Works with 3.3V and 5V systems
Low power consumption
Continuous battery backup
High-quality materials
Buying Guide Image

Frequently Asked Questions (FAQs)

1. Which has a real-time clock?

A real-time clock (RTC) is a battery-powered clock that is included in a microchip in a computer motherboard. This microchip is usually separate from the microprocessor and other chips and is often referred to simply as "the CMOS" (complementary metal-oxide semiconductor).

2. What does a real-time clock do?

A real-time clock (RTC) is an IC that keeps an updated track of the current time. This information can be read by a microprocessor, usually over a serial interface to facilitate the software performing functions that are time dependent.

3. Can a real-time clock be used as a system clock?

In some references, the term real-time clock is interchangeable with the term system clock . Within the context of this book, however, these terminologies are separate, as they are different on various architectures. Real-time clocks exist in many embedded systems and track time, date, month, and year.

4. What is the difference between real-time clock and system clock?

A key difference between an RTC and the system clock is that RTCs run even when the system is in a low power state (including "off"), and the system clock can't. Until it is initialized, the system clock can only report time since system boot ... not since the POSIX Epoch.

5. What are the benefits of real-time clock?

Benefits of RTCs include: RTC ICs have proved to be more precise than other methods — like programming the timer of the controller. It frees the main system from time-critical tasks. It has low power consumption and improved frequency stability.

Editor's Notes

During our real time clock research, we found 69 real time clock products and shortlisted 8 quality products. We collected and analyzed 3,865 customer reviews through our big data system to write the real time clocks list. We found that most customers choose real time clocks with an average price of £6.99.

The real time clocks are available for purchase. We have researched hundreds of brands and picked the top brands of real time clocks, including APKLVSR, AITRIP, DollaTek, DAOKAI, fasient1.

Written by
Harvey Wall Avatar

Harvey Wall was born and raised in Norwich. He mastered the art of tool production and finished at the prestigious Norwich University. His area of interest include cutting tools, abrasive finishing and power tools. Harvey is always looking for ways to improve the finesse of industrial tools via his myriads of researches. He also shares some of his experiences on many platforms while writing on tool products.