Increasing ESP32 AP max connections It has already been asked how many clients can connect to an ESP32 AP, but the answer is far from clear; the best one is from a year and half ago (ESP32 AP max connections: 4 or 10?) :


  The answer is as clear as any other EspressIf configuration data, it is 4 or maybe 5, or 8, or 12, 16 or even 20 (the same as a ESP8266!)


As I'm trying to move a project from the ESP8266 because it does not have enough AP connections, two questions can be asked :


what is the maximum number of AP connections supported by the 4.0 ESP-IDF framework ?
can it be increased in any way ?


Thank you.
After some extensive testing with several modules (not just blindly trusting the documentation), here's what I found.

Short answer : maximum 10 AP connections for the ESP32 running ESP-IDF 4.0 (updated around 1st of march 2020), and no, it can't be increased (easily).

Details :


The maximum number of AP connections is defined somewhere in libnet80211, and can't be modified since I have no access to the source code.
when the 11th station tries to connect, libnet80211 prints I (39682043) wifi: max connection, deauth!, more or less like the ESP8266 for the 5th station
Changine the ESP_WIFI_MAX_CONN_NUM (defined in esp_wifi_types.h:258) from 10 to anything else ends up in unpredictable behavior (I'm labelling this as unpredictable since without the libnet80211 code, it can't be reliably assessed).


I'm not giving up on increasing the number of stations yet, so maybe there'll be an update to this answer.