Does your application slow down as the number of users grows? Does your server sometimes stop responding during peak hours? Or are you wondering how to ensure high availability and avoid downtime? The solution is a load balancer – a tool that distributes traffic across multiple servers. It’s a foundation of modern web applications, SaaS services, and e-commerce platforms.

You can imagine it like cashiers in a supermarket. If the store has only one checkout and all customers line up there, a bottleneck forms. People get frustrated, some even leave without making a purchase. But if the store opens several checkouts and places an employee at the entrance to direct customers to the least busy line, shopping goes faster, queues are shorter, and the store serves more people. That employee directing customers is the load balancer. It “routes” internet traffic to several servers so none of them gets overloaded.

In this article, we’ll explain what a load balancer is, how it works, and why your company needs one.

What is a load balancer?

A load balancer is a system that distributes network or application traffic across multiple servers.

Thanks to this:

• no single server is overloaded,
• users enjoy fast and stable access,
• the application keeps running even if one server fails.

You could say the load balancer is the conductor of the server orchestra, keeping the whole system in harmony.

How does a load balancer work?

The load balancer acts as an intelligent intermediary between the user and the application servers. When someone opens a website or uses an app, their request first goes to the load balancer. It analyzes the situation—checks which servers are available and which ones are least loaded—and then decides where to forward the traffic. This way, no server gets overloaded, and the user receives a response instantly, without delays and without realizing there’s a whole orchestra of machines working in the background.

Popular load balancing algorithms:

• Round Robin – requests are distributed sequentially across servers.
• Least Connections – traffic is sent to the server with the fewest active connections.
• IP Hash – the same user is always directed to the same server, e.g., to maintain sessions.

Why does your application need a load balancer?

High availability

Without a load balancer, the failure of a single server can bring the application down. With a load balancer, traffic is automatically redirected to other servers. Your application runs without interruptions, and users don’t notice outages.

Scalability

As your application gains popularity, you add more servers. The load balancer automatically includes them in traffic distribution. Your app grows along with your business.

Better performance and speed

Balancing the load ensures no server is overwhelmed. That means shorter response times and a better user experience. Happy users are less likely to leave your service.

Security
 

A load balancer can add an extra layer of protection. It hides the real addresses of servers and filters certain types of attacks. Your application is harder to attack directly.

Cost optimization

Instead of investing in one powerful server, you can use several cheaper machines and distribute the traffic. Lower infrastructure costs, greater flexibility.

Types of load balancers

• Hardware load balancer

Dedicated physical devices. Powerful but expensive, used mainly in large data centers today.

• Software load balancer

Software running on standard servers. Popular solutions include HAProxy, Nginx, and Envoy. Ideal for companies developing web applications.

• Cloud load balancer

Services provided by cloud vendors, such as AWS Elastic Load Balancing, Azure Load Balancer, and Google Cloud Load Balancing.

Examples of load balancer use cases

• E-commerce stores – handling traffic spikes on Black Friday.
• SaaS applications – evenly distributing thousands of API requests.
• Banking systems – ensuring continuous availability of online services.
• Media and news portals – coping with traffic surges during live events.

How to know if your company needs a load balancer?

• Your application often slows down during peak hours.
• One server handles all requests.
• You want to prepare for business growth and more users.
• You experience downtime.
• You care about security and system resilience.
• If even one of these points applies, it’s time to implement a load balancer.

How to implement a load balancer in your company?

• Needs analysis – how many users you serve, which systems require scaling.
• Choosing a solution – hardware, software, or cloud-based load balancer.
• Configuring algorithms – selecting the right load balancing method.
• Performance testing – verifying the application runs smoothly under load.
• Monitoring – continuous oversight and optimization of settings.

Summary

A load balancer is no longer a luxury but a standard in building modern web applications. Thanks to it, your company gains reliability, scalability, speed, and security.

If your application aims to serve many clients and run without downtime – a load balancer is a necessity.

Looking for a trusted partner to implement and configure a load balancer? Contact Hawatel – we’ll advise, design the architecture, and deliver a solution tailored to your business.