We use cookies to help us improve, promote, and protect our services. By continuing to use the site, you agree to our cookie policy


Get inspiration to grow

Stay up to date with the latest marketing, sales and services 
tips and news from Voucherify.

Get inspiration to grow

arrow pointing left
go to blog
Promo strategies

How to Generate Unique Random Coupon Codes?

Mike Sędzielewski
Mike Sędzielewski
September 26, 2017
Share it on Twitter
Share it on Facebook
Share it on LinkedIn
Share it on Twitter
Share it on Facebook
Share it on LinkedIn

How to Generate Unique Random Coupon Codes?

Generating unique coupon codes is no easy task. How to ensure good customer experience, personalization, fraud protection, tracking of coupon redemptions and ROI? Read on to learn how to do just that.

What are unique vouchers?

Generating random coupon codes (unique number series or number and letter series) will help you with 1:1 tracking, marketing personalization, influencer management, affiliate sales management and fraud prevention.

Let’s start with the most obvious aspect, fraud protection. You clearly don’t want your vouchers to be easily forgeable. The key to generating hard-to-guess coupon codes is a large set of possible codes where only a small fraction of them is actually valid.

Random code generator

Customer experience and coupon redemption

How to improve the customer experience with coupon redemptions?

Once you make your codes un-guessable, you should think about customer experience. First of all, keep in mind there’s a trade-off between codes security (particularly length) and ease of use for the end user. It’s you who decides how to compromise these issues in your business reality. There are, however, a few general tips that should cut down on customer complaints without substantial security trade-off or too much development effort: 

  • Don’t make it too long - Usually, an 8-12 characters string should be un-guessable and unique enough.
  • Avoid ambiguous characters - It’s difficult to see the difference between O and 0 in the random string. I (upper case i) and l (lower case L) is even more tricky. We all recall the feelings when forced to try different combinations over and over again. So, you’d better prevent this before it hits your customer service team. Just exclude them from the character set. 
  • Cut the code into a few small parts, e.g. ABCD-1234-XYZ - It’s a subtle change but it simplifies typing at the checkout view. This adds up to the overall buying experience and customer satisfaction.

Vouchers tracking and ROI monitoring

It’s often the case that you run different voucher campaigns at the same time. Once they’re finished, the marketing team asks you for the performance reports. How many vouchers have been redeemed, what’s the number of failed redemptions, how many new customers have been acquired and so on. To handle different campaigns separately and to help further data crunching, it’s reasonable to extend your codes with a proper prefix or suffix from the first campaign. For example: XMAS-ABCD-1234. 

You can also add metadata to the campaigns, more about it here.

And here comes the gift

If you need to generate unique coupon codes, passwords or any unique numbers strings, especially when needed in bulk, we have good news; we open sourced a library that generates un-guessable coupon codes. It’s free of charge!

Random code generator from Voucherify  – it’s pretty flexible and enables all the small hacks we shared above (length, charset, prefix, suffix, and pattern).

It can generate an unlimited amount of codes in batches! The generated codes can be used as random promotional codes, serial numbers, strong passwords, sweepstake codes, pin codes, voucher redeem codes and much more.


Launch disgustingly effective coupon campaigns with Voucherify

Start now


Share it on Twitter
Share it on Facebook
Share it on LinkedIn
Mike Sędzielewski
Co-founder of Voucherify and rspective. Fan of API-solutions for marketing automation and headless approach in digital marketing and sales. In private, he enjoys reportage and everything non-fiction.
More articles by this author

Join our newsletter

By registering, you confirm you have read and agree to the Subscription Agreement, and to the storing and processing of your personal data by Voucherify as described in the Privacy Policy.
Before you send us your data, you must become acquainted with the Privacy Policy where you will find information on the personal data controller, your rights and our obligations, the purpose for which your data are processed and any other information which relates to the protection and security of your personal data.
Thank you for subscribing to our newsletter!
Something went wrong while submitting the form.

Are you wasting time and money on digital promotions?

It’s time for a change.