# Quantum Keycodes

Quantum keycodes allow for easier customization of your keymap than the basic ones provide, without having to define custom actions.

All keycodes within quantum are numbers between `0x0000` and `0xFFFF`. Within your `keymap.c` it may look like you have functions and other special cases, but ultimately the C preprocessor will translate those into a single 4 byte integer. QMK has reserved `0x0000` through `0x00FF` for standard keycodes. These are keycodes such as `KC_A`, `KC_1`, and `KC_LCTL`, which are basic keys defined in the USB HID specification.

On this page we have documented keycodes between `0x00FF` and `0xFFFF` which are used to implement advanced quantum features. If you define your own custom keycodes they will be put into this range as well.

## QMK Keycodes

|Key            |Aliases    |Description                                                          |
|---------------|-----------|---------------------------------------------------------------------|
|`RESET`        |           |Put the keyboard into DFU mode for flashing                          |
|`DEBUG`        |           |Toggle debug mode                                                    |
|`EEPROM_RESET` |`EEP_RST`  |Resets EEPROM state by reinitializing it                             |
|`KC_GESC`      |`GRAVE_ESC`|Escape when tapped, <code>&#96;</code> when pressed with Shift or GUI|
|`KC_LEAD`      |           |The [Leader key](feature_leader_key.md)                              |
|`KC_LOCK`      |           |The [Lock key](feature_key_lock.md)                                  |