What is a FIFO queue?

A FIFO queue is a queue that operates on a first-in, first-out (FIFO) principle. This means that the request (like a customer in a store or a print job sent to a printer) is processed in the order in which it arrives. A first-come, first-served line is the most common type of queue that we join in our everyday lives and is generally accepted as the fairest way to operate a queue.

In queuing theory, the rule governing queue operation is known as queuing discipline. Besides first-in-first-out, other queuing disciplines include last-in-first-out, prioritized, and serve-in-random-order.  

The online queues in Queue-it’s virtual waiting room are based on the first-in, first-out queuing discipline.

Queue-it's virtual waiting room

How does first-in, first-out online queuing work?

Just like when a store or restaurant reaches capacity and people line up outside, Queue-it’s virtual waiting room places visitors in an online queue when your website or app reaches capacity. Unlike CDN visitor prioritization tools, Queue-it has a centralized overview of traffic requests to your website, allowing the tool to identify visitors with a timestamp and give each person a unique, sequential queue id. Based on a users-per-minute inflow setting, you then throttle visitors back to your website or app in a fair, first-in-first-out order.

how a FIFO online queue works

Why use a FIFO queue online?

Orange bowling balls headed towards bowling pin

Online traffic can overwhelm your site or app

51%

of IT outages are avoidable, say global IT decision makers, with usage spikes being the number two reason behind downtime

65%

of enterprises need over an hour to fix a website

86%

of enterprises report downtime costs of $300,000+ per hour

Online queuing prevents website crashes from high demand

When running your biggest sales, the price for website failure is high. You need to get them right.


A FIFO online queue system gives you control over online traffic peaks that threaten to crash your site. Placing visitors in a first-in, first-out online queue keeps your website performing its best when it matters most.

Pile of green progress bar icons to an ordered FIFO queue
Pile of green progress bar blocks going through Queue-it's virtual waiting room

A FIFO queue delivers online fairness

No matter where you are in the world, a FIFO queue is accepted as the golden standard of fairness.


There are unfair and arbitrary ways to deal with heavy online traffic. Some waiting room solutions handle traffic as page requests, not people, and have a decentralized view of traffic. In practice, this means that how quickly visitors get through to your website depends on traffic levels in their area, undermining fairness.


Queue-it’s virtual waiting room has a centralized overview of all traffic to get the order right, helping you ensure a positive customer experience and maintain your brand integrity.

A FIFO queue taps into queue psychology

The latest studies in queue psychology show that what matters most is not how long the wait is but how we feel when we wait. The perception of fairness has arguably the biggest impact on how we feel when we’re waiting in line. Think of the last time you waited in line—we’re constantly on guard to ensure no one cuts the line.

Knowing that a queue operates based on the first-come, first-served principle— and seeing transparent wait info that shows it—relieves anxiety that could otherwise lead to a negative user experience.

Queue-it's customizable queue page
Red ball rolling down green stairs

A FIFO queue helps boost conversion rates

It’s true that with a virtual queuing solution not all visitors wanting to access your site will be able to. But remember, the alternative is that your website crashes and no one can access it.

Customers who wait will be most driven to buy, raising your conversion rates. And FIFO online queues show visitors how popular a product is. By being provided a queue number and fair, transparent wait information, visitors know and see that what they are waiting for is also valuable to others.

When is it helpful to use FIFO online queuing?

Product launches & releases
In-demand online ticket sales
University admissions
Government applications

Tickets are emotive, people have a connection to the product. Very often, it’s something they have been planning to buy and waiting for the onsale to happen. Our customers needed to ensure it’s a fair buying process for those who want tickets. The queue gives a professional experience to the onsale.

Sean Hanly, CEO, TicketSolve

Queue-it quote from Sean Hanly, CEO, TicketSolve

Discover how FIFO queuing helps you prevent your website from crashing