CloudFormation Diagram Generator — Visualize AWS Templates Instantly

InfraSketch now supports CloudFormation. Paste a CloudFormation YAML or JSON template — including all the !Ref, !GetAtt, and !Sub shorthand you're used to writing — and get a clean architecture diagram in seconds. No login, no backend, everything runs in your browser.

Why CloudFormation support matters

CloudFormation is still the most widely deployed IaC tool in AWS-heavy organizations. It ships with every AWS account, it integrates natively with CDK, SAM, and AWS Service Catalog, and most platform teams have years of existing templates they maintain. But CloudFormation has always been terrible at communicating what it actually does. A 400-line YAML file is not an architecture — it's a specification. Turning it into a diagram has always meant manual work in draw.io or Lucidchart.

InfraSketch eliminates that step. Paste the template, click Generate, get a diagram you can share or export.

How it works

CloudFormation templates use YAML shorthand tags like !Ref and !GetAtt that are not standard YAML — most parsers choke on them. InfraSketch registers custom YAML types for all CloudFormation intrinsic functions before parsing, so your templates load cleanly without any preprocessing.

Once parsed, the engine walks every resource's Properties block and:

• Maps the Type field (e.g. AWS::ECS::Service) to a visual category with the correct AWS icon
• Detects VpcId: !Ref MyVPC and draws the resource inside the VPC container
• Detects SubnetId / SubnetIds / Subnets references and places the resource in the correct subnet lane
• Infers directed connections from any other Ref or GetAtt between supported resources

The result is the same zoned layout InfraSketch uses for Terraform — Internet zone at the top, ingress layer, VPC with subnets, data zone, messaging zone, security zone — all inferred automatically from your template.

Quick start

1. Open infrasketch.cloud
2. Click the CloudFormation tab
3. Paste your template (YAML or JSON) and click Generate Diagram
4. Export as PNG, SVG, or draw.io XML — or click Share to copy a shareable URL

The parser auto-detects YAML vs JSON based on whether the template starts with {.

Example: a minimal web stack

AWSTemplateFormatVersion: '2010-09-09'
Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: 10.0.0.0/16

  PublicSubnet:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref VPC
      CidrBlock: 10.0.1.0/24

  AppLoadBalancer:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Subnets:
        - !Ref PublicSubnet

  AppFunction:
    Type: AWS::Lambda::Function
    Properties:
      Role: !GetAtt LambdaRole.Arn
      Environment:
        Variables:
          QUEUE_URL: !Ref AppQueue

  AppQueue:
    Type: AWS::SQS::Queue

  LambdaRole:
    Type: AWS::IAM::Role

This produces a diagram with the VPC container, PublicSubnet with the ALB inside, Lambda connecting to SQS and IAM Role, and the messaging zone for the queue — all from the references in the template.

Supported resource types

What gets inferred automatically

Intrinsic functions supported

The YAML parser handles all standard CloudFormation shorthand tags without requiring you to expand them to long form:

• !Ref — logical resource reference
• !GetAtt — attribute reference (!GetAtt Resource.Attribute or list form)
• !Sub — string substitution (scalar and list forms)
• !If, !And, !Or, !Not — conditionals
• !Select, !Join, !Split, !FindInMap
• !Base64, !ImportValue, !Condition

JSON templates are also supported — { "Ref": "MyVPC" } and { "Fn::GetAtt": ["MyRole", "Arn"] } both work exactly the same way.

What's still Terraform-only

A few features remain Terraform-specific for now: module expansion (ZIP upload and registry auto-fetch), and the plan JSON workflow. CloudFormation doesn't have an equivalent to terraform show -json, but the template itself is already the resolved source of truth — there's no variable evaluation step needed.

Use cases

• Code reviews — paste the template diff, see what changed in the diagram
• Onboarding — new team member needs to understand the stack without reading 500 lines of YAML
• Documentation — export as PNG or SVG and embed in a wiki, Confluence page, or design doc
• draw.io integration — export as draw.io XML to get a fully editable diagram in diagrams.net or Confluence
• Audit prep — show reviewers the actual infrastructure topology without sharing credentials