Is this tool free to use?

Yes. The Load Balancer Design Tool is completely free with no signup required, no usage limits, and no ads. Everything runs in your browser — your architecture designs are never uploaded to any server.

What is the difference between Layer 4 and Layer 7 load balancing?

Layer 4 (transport) load balancing routes traffic based on IP address and TCP/UDP port without inspecting packet contents. Layer 7 (application) load balancing can make routing decisions based on HTTP headers, URLs, cookies, and request content. NGINX and HAProxy support both, while AWS NLB is Layer 4 only and AWS ALB is Layer 7 only.

How do health checks work in load balancer configurations?

Health checks are periodic requests the load balancer sends to backend servers to verify they are running. If a server fails consecutive health checks, the load balancer stops routing traffic to it. When the server recovers, traffic resumes automatically. You can configure the check path, interval, and timeout in the settings panel.

Can I design Kubernetes ingress architectures with this tool?

Yes. The tool includes a dedicated Kubernetes preset with ingress controllers, services, and pods. You can also combine Kubernetes components with external load balancers, CDNs, and databases to model your complete infrastructure including cloud-managed services.

What is SSL termination and should I enable it?

SSL termination means the load balancer handles encrypting and decrypting HTTPS traffic, so backend servers receive plain HTTP. This offloads CPU-intensive TLS work from your application servers and simplifies certificate management. Enable it for most production setups unless your compliance requirements demand end-to-end encryption.

Load Balancer Design Tool - Generate Nginx, HAProxy, Caddy & F5 Configs

Why Use This Load Balancer Design Tool?

Designing a load balancer architecture is a critical step in building scalable, fault-tolerant systems. This visual tool lets you drag and drop components, connect services, and generate production-ready configuration files — all from your browser.

Whether you're building a simple HTTP setup or a complex microservices architecture with CDN, WAF, API gateways, and database clusters, this tool helps you visualize and validate your design before deploying. It generates configurations for NGINX, HAProxy, and Caddy, plus Docker Compose and Terraform templates.

Key Features

Visual Canvas — Drag-and-drop nodes for load balancers, servers, databases, caches, CDNs, and more.
20 Architecture Presets — Start from battle-tested templates: microservices, Kubernetes, zero trust, GraphQL federation, and more.
Real-Time Validation — Get warnings for single points of failure, missing health checks, and no SSL.
Config Generation — Export NGINX, HAProxy, Caddy, Docker Compose, and Terraform configs.
Cost Estimation — See estimated monthly costs for each component in your architecture.
Technology Tooltips — Learn about each technology's strengths, weaknesses, and best use cases.

The Load Balancer Design Tool is a free, browser-based visual editor for planning and documenting your server infrastructure. Whether you are setting up a simple two-server HTTP backend or engineering a multi-region microservices platform, this tool lets you drag and drop real-world components onto a canvas, wire them together, and generate production-ready configuration files in seconds. It supports output for NGINX, HAProxy, Caddy, and F5 BIG-IP, plus Docker Compose and Terraform templates you can deploy immediately. If you also need to map out your database schema, try the ER Diagram Designer, or use the Architecture Diagram tool for broader system diagramming.

With 27 built-in architecture presets covering patterns like Kubernetes clusters, GraphQL Federation, zero-trust networking, AI inference pipelines, and event-driven systems, you never start from a blank canvas unless you want to. Each preset is a fully connected, annotated reference architecture you can customize to match your exact requirements. The real-time validation engine checks for single points of failure, missing health checks, absent SSL on public endpoints, and disconnected components, so you catch design flaws before they become production incidents. Pair it with the Subnet Calculator when planning IP address ranges, or run your domain through the SSL Certificate Checker to verify your TLS setup after deployment.

Everything runs entirely in your browser. No data is uploaded, no account is required, and there are no usage limits. You can export your architecture as a shareable link, a JSON snapshot for version control, a high-resolution PNG for documentation, or an animated GIF that walks through the topology. The integrated cost estimator gives you a monthly price breakdown for each component, helping you budget before you provision a single instance. For network-level planning, check the Port Reference Guide or perform a DNS Lookup to validate your domain configuration.

How It Compares

NGINX vs HAProxy vs Caddy is the most common decision when choosing an open-source load balancer. NGINX is the most widely deployed option, excelling at HTTP reverse proxying, static file serving, and SSL termination with minimal memory usage. HAProxy is purpose-built for high-throughput load balancing and offers advanced health checks, real-time stats dashboards, and Layer 4 TCP support that NGINX lacks in its open-source version. Caddy stands out for its automatic HTTPS with zero-configuration certificate management, making it ideal for smaller deployments where simplicity is the top priority. For enterprise environments, F5 BIG-IP provides hardware-accelerated performance, iRules scripting, and compliance-grade security at a premium price point.

Cloud-managed alternatives like AWS ALB, Azure Application Gateway, and GCP Cloud Load Balancing eliminate operational overhead but introduce vendor lock-in and can become expensive at scale. This tool lets you visually compare all of these options by placing them on the same canvas, wiring them to your backend services, and examining the generated configurations side by side before you commit to a technology stack.

Frequently Asked Questions

What is a load balancer and why do I need one?

A load balancer distributes incoming network traffic across multiple servers. It ensures high availability and reliability by sending requests only to healthy servers. You need one when your application receives more traffic than a single server can handle, or when you need zero-downtime deployments.

Which load balancer should I choose — NGINX, HAProxy, or Caddy?

NGINX is the most popular choice for HTTP load balancing with excellent performance and a huge community. HAProxy is preferred for high-performance TCP/HTTP load balancing with advanced health checks. Caddy is great for simple setups with automatic HTTPS certificate management. For AWS environments, consider ALB or NLB for fully managed solutions.

What load balancing algorithm should I use?

Round Robin works well for most cases with equally capable servers. Use Least Connections when servers have varying capacity or request processing times. Use IP Hash when you need session persistence without cookies. Weighted Round Robin lets you route more traffic to stronger servers.

How do I use the architecture canvas?

Drag components from the left palette onto the canvas. Connect nodes by dragging from one node's handle to another. Click any node to edit its properties in the right panel. Select a preset to load pre-built architectures, or build your own from scratch. Use the bottom bar to validate your design, estimate costs, and export configurations.

Can I export my architecture design?

Yes! You can export your design in multiple formats: JSON (to save and reimport later), Docker Compose (docker-compose.yml), Terraform (main.tf for AWS infrastructure), and PNG image. You can also share your design via a link that encodes the full diagram state in the URL.

Rate This Tool

Get Weekly Tools

Join 10,000+ users getting our tool updates.