![\"Get](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2021\/01\/Get-Epoch-Unix-Time-ESP32-tutorial-Arduino.jpg.jpg?resize=1200%2C675&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\nIf you want to get date and time in a human readable format, we recommend the following tutorial instead: <\/p>\n\n\n\n
- ESP32 NTP Client-Server: Get Date and Time (Arduino IDE)<\/a><\/li><\/ul>\n\n\n\n
What is epoch time?<\/h2>\n\n\n\n
The Epoch Time<\/strong> (also know as Unix epoch,<\/strong> Unix time<\/strong>, POSIX time<\/strong> or Unix timestamp)<\/strong> is the number of seconds that have elapsed since January 1, 1970 (midnight UTC\/GMT), not counting leap seconds (in ISO 8601: 1970-01-01T00:00:00Z).<\/p>\n\n\n\n
NTP (Network Time Protocol)<\/h2>\n\n\n\n
NTP stands for Network Time Protocol and it is a networking protocol for clock synchronization between computer systems. In other words, it is used to synchronize computer clock times in a network.<\/p>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2021\/01\/ESP32-NTP-Client-Server.png?resize=1024%2C564&quality=100&strip=all&ssl=1\")
<\/figure>\n\n\n\nThere are NTP servers like pool.ntp.org<\/em> that anyone can use to request time as a client. In this case, the ESP32 is an NTP Client that requests time from an NTP Server (pool.ntp.org)<\/em>.<\/p>\n\n\n\n
ESP32 Get Epoch\/Unix Time Function<\/h2>\n\n\n\n
To get epoch\/unix time with the ESP32, you can use the following function getTime()<\/span>:<\/p>\n\n\n\n
\/\/ Function that gets current epoch time\nunsigned long getTime() {\n time_t now;\n struct tm timeinfo;\n if (!getLocalTime(&timeinfo)) {\n \/\/Serial.println(\"Failed to obtain time\");\n return(0);\n }\n time(&now);\n return now;\n}<\/code><\/pre>\n\n\n\nThis function returns the current epoch time. Continue reading for a complete example.<\/p>\n\n\n\n
ESP32 Get Epoch\/Unix Time Example<\/h2>\n\n\n\n
Copy the following code to your Arduino IDE. This code connects to the internet and requests the time from an NTP server (pool.ntp.org<\/em>).<\/p>\n\n\n
\/*\n Rui Santos\n Complete project details at https:\/\/RandomNerdTutorials.com\/epoch-unix-time-esp32-arduino\/\n \n Permission is hereby granted, free of charge, to any person obtaining a copy\n of this software and associated documentation files.\n \n The above copyright notice and this permission notice shall be included in all\n copies or substantial portions of the Software.\n*\/\n\n#include <WiFi.h>\n#include "time.h"\n\n\/\/ Replace with your network credentials\nconst char* ssid = "REPLACE_WITH_YOUR_SSID";\nconst char* password = "REPLACE_WITH_YOUR_PASSWORD";\n\n\/\/ NTP server to request epoch time\nconst char* ntpServer = "pool.ntp.org";\n\n\/\/ Variable to save current epoch time\nunsigned long epochTime; \n\n\/\/ Function that gets current epoch time\nunsigned long getTime() {\n time_t now;\n struct tm timeinfo;\n if (!getLocalTime(&timeinfo)) {\n \/\/Serial.println("Failed to obtain time");\n return(0);\n }\n time(&now);\n return now;\n}\n\n\/\/ Initialize WiFi\nvoid initWiFi() {\n WiFi.mode(WIFI_STA);\n WiFi.begin(ssid, password);\n Serial.print("Connecting to WiFi ..");\n while (WiFi.status() != WL_CONNECTED) {\n Serial.print('.');\n delay(1000);\n }\n Serial.println(WiFi.localIP());\n}\n\nvoid setup() {\n Serial.begin(115200);\n initWiFi();\n configTime(0, 0, ntpServer);\n}\n\nvoid loop() {\n epochTime = getTime();\n Serial.print("Epoch Time: ");\n Serial.println(epochTime);\n delay(1000);\n}\n<\/code><\/pre>\n\tView raw code<\/a><\/p>\n\n\n\n
Insert your network credentials in the following variables and the code will work straight away:<\/p>\n\n\n\n
\/\/ Replace with your network credentials\nconst char* ssid = \"REPLACE_WITH_YOUR_SSID\";\nconst char* password = \"REPLACE_WITH_YOUR_PASSWORD\";<\/code><\/pre>\n\n\n\nHow the Code Works<\/h3>\n\n\n\n
Let’s take a quick look on how the code works.<\/p>\n\n\n\n
Libraries<\/h4>\n\n\n\n
First, you need to include the WiFi<\/span> library to connect the ESP32 to your local network; and the time<\/span> library to handle time structures.<\/p>\n\n\n\n
#include <WiFi.h>\n#include \"time.h\"<\/code><\/pre>\n\n\n\nNetwork Credentials<\/h4>\n\n\n\n
Insert your network credentials in the following variables so that the ESP32 can connect to your network.<\/p>\n\n\n\n
\/\/ Replace with your network credentials\nconst char* ssid = \"REPLACE_WITH_YOUR_SSID\";\nconst char* password = \"REPLACE_WITH_YOUR_PASSWORD\";<\/code><\/pre>\n\n\n\nNTP Server<\/h4>\n\n\n\n
We\u2019ll request the time from pool.ntp.org<\/em>, which is a cluster of timeservers that anyone can use to request the time.<\/p>\n\n\n\n
const char* ntpServer = \"pool.ntp.org\";<\/code><\/pre>\n\n\n\ngetTime() function<\/h4>\n\n\n\n
The getTime()<\/span> function gets and returns the current epoch time. If it is not able to get the time, it returns 0<\/span>.<\/p>\n\n\n\n
\/\/ Function that gets current epoch time\nunsigned long getTime() {\n time_t now;\n struct tm timeinfo;\n if (!getLocalTime(&timeinfo)) {\n \/\/Serial.println(\"Failed to obtain time\");\n return(0);\n }\n time(&now);\n return now;\n}<\/code><\/pre>\n\n\n\ninitWiFi()<\/h4>\n\n\n\n
The initWiFi()<\/span> function initializes Wi-Fi and connects the ESP32 to your local network.<\/p>\n\n\n\n
void initWiFi() {\n WiFi.mode(WIFI_STA);\n WiFi.begin(ssid, password);\n Serial.print(\"Connecting to WiFi ..\");\n while (WiFi.status() != WL_CONNECTED) {\n Serial.print('.');\n delay(1000);\n }\n Serial.println(WiFi.localIP());\n}<\/code><\/pre>\n\n\n\nsetup()<\/h4>\n\n\n\n
In the setup()<\/span>, initialize the Serial Monitor at a baud rate of 115200.<\/p>\n\n\n\n
Serial.begin(115200);<\/code><\/pre>\n\n\n\nCall the initWiFi()<\/span> function to initialize Wi-Fi:<\/p>\n\n\n\n
initWiFi();<\/code><\/pre>\n\n\n\nConfigure the time using the configTime()<\/span> function. The first and second arguments correspond to the GMT time offset and daylight saving time. However, because we’re interested in getting epoch time, these arguments should be 0<\/span>. The last argument is the NTP server (ntpServer<\/span>):<\/p>\n\n\n\n
configTime(0, 0, ntpServer);<\/code><\/pre>\n\n\n\nloop()<\/h4>\n\n\n\n
In the loop()<\/span>, get the epoch time and save it in the epochTime<\/span> variable:<\/p>\n\n\n\n
epochTime = getTime();<\/code><\/pre>\n\n\n\nFinally, print the epoch time every second:<\/p>\n\n\n\n
Serial.print(\"Epoch Time: \");\nSerial.println(epochTime);\ndelay(1000);<\/code><\/pre>\n\n\n\nDemonstration<\/h2>\n\n\n\n
Upload the code to your ESP32 board. Then, open the Serial Monitor at a baud rate of 115200. Press the ESP32 on-board RST button. It should connect to Wi-Fi and start printing the current epoch\/unix time every second.<\/p>\n\n\n\n
![\"ESP32](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2021\/01\/ESP32-Get-Epoch-Time-Example-Serial-Monitor.png?resize=669%2C445&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\nWrapping Up<\/h2>\n\n\n\n
This was a quick guide showing you how to get epoch\/unix time with the ESP32. The epoch time is the number of seconds elapsed since January 1 1970. To get time, we need to connect to an NTP server, so the ESP32 needs to have access to the internet.<\/p>\n\n\n\n
If you’re interested in getting date and time in a human readable format, refer to the next tutorial: <\/p>\n\n\n\n
- ESP32 NTP Client-Server: Get Date and Time (Arduino IDE)<\/a><\/li><\/ul>\n\n\n\n
We hope you’ve found this tutorial useful. If you want to learn more about the ESP32, check our resources:<\/p>\n\n\n\n
- Learn ESP32 with Arduino IDE<\/a><\/li>
- Build Web Servers with ESP32 and ESP8266<\/a><\/li>
- More ESP32 Projects and Tutorials\u2026<\/a><\/li><\/ul>\n\n\n\n
Thanks for reading.<\/p>\n","protected":false},"excerpt":{"rendered":"
This quick guide shows how to get epoch\/unix time using the ESP32 board with Arduino IDE. Getting the epoch time can be useful to timestamp your readings, give unique names … <\/p>\n
- Build Web Servers with ESP32 and ESP8266<\/a><\/li>
- Learn ESP32 with Arduino IDE<\/a><\/li>
- ESP32 NTP Client-Server: Get Date and Time (Arduino IDE)<\/a><\/li><\/ul>\n\n\n\n