# What is a cold start?

A cold start is the delay when a platform must start your code before answering a request.

## The short version

A cold start is the delay when a platform must start your code before answering a request. It happens with serverless functions and with free services that sleep after inactivity. The delay may be small or may last up to a minute. Apps that stay running do not have this delay, apart from when they are redeployed.

## On EasyHost

EasyHost apps do not sleep when idle. [Learn more](/products/app-hosting).