What Is A Passcode?

Date First Published: 8th November 2023

Topic: Cybersecurity

Subtopic: Security Mechanisms & Technologies

Computer Terms & Definitions

Difficulty: Easy

Difficulty Level: 3/10

CONTENTS

What Makes A Strong Passcode?
Security Of Passcodes

Learn about what a passcode is in this article.

A passcode is a string of numbers used to authenticate a user before signing into an electronic account or electronic device. It is similar to a password, but only contains numbers and is limited to a smaller character limit of 3-8 characters. Passcodes provide quick and easy authentication on devices with a numeric keypad, such as ATMs, electronic safes, and locked doors in buildings.

What Makes A Strong Passcode?

A strong passcode should:

Contain at least 4 characters. The more characters a passcode contains, the more possible combinations there are, making it stronger. For example, a four-digit passcode can have 10,000 different combinations, whilst a 6-digit passcode can have 1,000,000 different combinations.
Not be easily guessable. When hackers try to guess a passcode, through a brute-force attack, or manually, the first passcodes they try are obvious and easily guessable passcodes. For example, passcodes like '1111' or '9999' can easily be guessed.
Not be a previously used passcode. Reusing passcodes across multiple devices is risky. If a passcode was correctly discovered, they might try the same passcode on other devices.

Security Of Passcodes

Like passwords, passcodes provide the minimum layer of security for an account by only allowing access if the correct numeric code is entered and denying access if the passcode is incorrect. However, the security of passcodes cannot 100% guarantee no unauthorised access. Especially if easily guessed passcodes are used and someone performed a brute-force attack, the correct passcode could be found, allowing a hacker to gain unauthorised access to an electronic device or account.

Passcodes are less secure than passwords or passphrases because they only contain numbers. To prevent passcodes from being guessed, devices that provide passcode authentication, like iPhones, temporarily block access after a certain number of failed attempts. For example, after three failed attempts, users may be locked out for 5 minutes.