5 Types of Input Validation

John Spacey, updated on April 17, 2017

Input validation is a systematic check that rejects or accepts data based on a set of rules. It is a basic software coding practice that is performed before processing user input or data from untrusted systems. The following are common types of input validation.

Correctness

Basic checks that data conforms to its data type. For example, checking that an order quantity is numeric.

Business Rules

Checking the correctness of the data based on business rules. For example, validating that a reservation request for a flight occurs in the future at least 12 hours from the current time.

Warnings

Validations typically include both strict validations of data and warnings that can be bypassed by users. For example, a hotel booking site might warn a customer that a hotel is under construction during the period of their stay before finalizing a booking.

Information Security

Checking data for information security threats.

Risk Controls

Input validations are a common way to implement risk controls. For example, a financial trading system may prevent orders beyond a certain dollar amount authorized for each trader.

Overview: Input Validation
Type	Coding Software Design IT Controls
Definition	A systematic check that rejects or accepts data based on a set of rules.
Related Concepts	Information Security User Interface Design Risk Controls IT Controls Coding Business Rules Requirements