Comments on: Generating a Software License Key String with PHP

By: Sajjad Hossain

Sajjad Hossain — Fri, 25 Jan 2019 14:05:00 +0000

I have created one like this

$license = rand(1000,9999) . '-' . rand(1000,9999) . '-' . rand(1000,9999) . '-' . rand(1000,9999) . '-' . rand(1000,9999);

I have already using in my project to generate and validate purchased user. Here is details

By: Silver Moon

Silver Moon — Wed, 14 Oct 2015 13:58:00 +0000

$segment .= $tokens[ rand(0, strlen($tokens)-1) ];

By: Rohan

Rohan — Mon, 01 Dec 2014 10:55:00 +0000

Thank you very much

By: redwall_hp

redwall_hp — Fri, 22 Feb 2013 06:20:29 +0000

The key is guaranteed unique by way of the second code block. Before storing the key in the database, a while loop ensures that the key hasn’t already been assigned to a record.

Crypt() is another solution, possibly a better solution, but sometimes you want to make sure that the string is easy to read out loud or type manually.

By: Tran Ngoc Tuan Anh

Tran Ngoc Tuan Anh — Thu, 21 Feb 2013 05:56:30 +0000

While your method guarantees that the key is random, it doens’t guarantee that 2 users have the same key (uniqueness). Why don’t you use something simple like crypt() function. It’s fast, simple and strong enough.

By: Blaine Moore

Blaine Moore — Sat, 16 Feb 2013 13:06:14 +0000

Another way you could improve it is to use the last 5 characters as a checksum for the rest of the string (potentially with a salt) if there might ever be a need for validating the API key w/o a net connection to the server.