Can I power ESP8266 with more than 3.5 V? I am concerned whether I need to use a voltage divider to power my ESP8266 module. My concerns stem from the warnings that I have heard in multiple tutorials. Everyone seems to regard the ESP8266 as being very sensitive to supply voltage. 

Has anyone use the ESP8266 with an supply voltage greater than 3.5 V? What were the effects? Is it even necessary to make a voltage divider?

I am asking because my application has limited real estate.
The datasheet usually is definitive on the allowable range of voltages.

Look in Section 5.1: Electrical Characteristics.

Working Voltage Value:


Min: 2.5 V
Typical: 3.3 V
Max: 3.6 V


If you have to feed in signals that could go higher than 3.3 V in normal operation, you need to either clamp it with Zener diodes, or use a voltage divider. 

If you are asking about powering the chip with more than 3.3 V, don't. You can get away with a 3.3 V linear regulator and 2 capacitors so that you are powering it with no more than designed supply voltage.