Don't send 5 V signals to your ESP8266. The use of an ESP8266 with Arduino requires logic level translation of the UART signal, as provided by this easy 3.3 V - 5 V adapter. It makes the ESP-01 ESP8266 WiFi module (150445-91) the easiest WiFi transceiver for your Arduino (5 V).
Adapter module for ESP-01 Wi-Fi module
3.3 V Voltage Regulator Circuit & Onboard Level Conversion for easy use of 5 V microcontroller with ESP-01 Wi-Fi Module
Compatible with UNO R3
4.5 ~ 5.5 V (on-board 3.3 V LDO Regulator)
Interface Logic Voltage : 3.3 V / 5 V Compatible (on-board level shift)
Current : 0 - 240 mAV
Additional Information
Device
Convertor
Type
ESP8266 | UART | Logic Level
Unlock seamless connectivity with the HKD ESP8266 ESP-01 ADAPT 3.3V/5V adapter. This essential logic level converter ensures safe communication between your Arduino and ESP-01 Wi-Fi module, providing reliable performance for all your IoT projects. Enjoy easy integration and enhanced functionality with this durable, high-quality adapter designed for optimal efficiency.