ESP8266 Community Forum

Hello guys, i want to ask if is it ok to power supply NodeMcu esp8266 with mini-usb connector right into electricity socket using phone charger adapter.

No. ESP8266 requires 3.3 volts, USB wall wart is 5.
But if you are capable you can modify the USB power supply. I have converted three of them by replacing the regulator zener diode with a smaller voltage one. It's sort of trial and error. You need something between 1.7 and 2.3 v. Output voltage is defined by the sum of voltage across the zener and a optical isolator.

I think this was asking specifically about the NodeMCU Devkit style boards which have a micro usb and regulator on the board - yes its fine to plug that directly into a phone charger to power the esp.