---
title: Combo Configuration
sidebar_label: Combos
---
See the [Combos feature page ](../features/combos.md ) for more details and examples.
See [Configuration Overview ](index.md ) for instructions on how to change these settings.
## Kconfig
Definition file: [zmk/app/Kconfig ](https://github.com/zmkfirmware/zmk/blob/main/app/Kconfig )
| Config | Type | Description | Default |
| ------------------------------------- | ---- | -------------------------------------------------------------- | ------- |
| `CONFIG_ZMK_COMBO_MAX_PRESSED_COMBOS` | int | Maximum number of combos that can be active at the same time | 4 |
| `CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY` | int | Maximum number of active combos that use the same key position | 5 |
| `CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO` | int | Maximum number of keys to press to activate a combo | 4 |
If `CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY` is 5, you can have 5 separate combos that use position `0` , 5 combos that use position `1` , and so on.
If you want a combo that triggers when pressing 5 keys, you must set `CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO` to 5.
## Devicetree
Applies to: `compatible = "zmk,combos"`
Definition file: [zmk/app/dts/bindings/zmk,combos.yaml ](https://github.com/zmkfirmware/zmk/blob/main/app/dts/bindings/zmk%2Ccombos.yaml )
The `zmk,combos` node itself has no properties. It should have one child node per combo.
Each child node can have the following properties:
| Property | Type | Description | Default |
| --------------- | ------------- | ----------------------------------------------------------------------------------------------------- | ------- |
| `bindings` | phandle-array | A [behavior ](../features/keymaps.md#behaviors ) to run when the combo is triggered | |
| `key-positions` | array | A list of key position indices for the keys which should trigger the combo | |
| `timeout-ms` | int | All the keys in `key-positions` must be pressed within this time in milliseconds to trigger the combo | 50 |
| `slow-release` | bool | Releases the combo when all keys are released instead of when any key is released | false |
| `layers` | array | A list of layers on which the combo may be triggered. `-1` allows all layers. | `<-1>` |
The `key-positions` array must not be longer than the `CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO` setting, which defaults to 4. If you want a combo that triggers when pressing 5 keys, then you must change the setting to 5.
