Perseid Modeler

JSON Schema editor and OpenAPI modeling tool

JSON Schema editor and OpenAPI modeling tool

What you can do
with Perseid Modeler?

Draw diagrams
Define JSON schema, or OpenAPI schema visually.
Define specifics
Directly or using the visual Specification assistant.
Export to PDF
Share pixel-perfect diagrams in printable format.
Generate scripts
Preview and save JSON schema code or OpenAPI scripts.
OpenAPI schema design and data modeling

JSON schema editor & OpenAPI schema designer

Design your schema visually. Use the dropdown menu to create specific nodes for both JSON schema and OpenAPI. Perseid Modeler will recognize where you are in the schema and offer you a menu to create appropriate nested objects. Read quick start guides for:

JSON schema modeling OpenAPI design

Specification assistant

  • Define specifications using code or the Specification assistant.
  • The assistant displays the predefined properties and allows you to fill in only the values.
  • The assistant is available both in the right sidebar and in the modal dialog.
  • After entering a value, the code in the Specifications field is automatically updated.
Specification assistant for JSON schema properties
JSON schema or OpenAPI ER diagram

Tree & ERD-like diagrams

  • Every project automatically has two diagrams that you can switch between.
  • In a tree diagram there is a fixed structure of objects.
  • You can add labels, images, lines and so on to an ERD-like diagram.
  • Subschemas can be easily hidden.

UI & Display modes

  • Support for displaying various details in the tree diagram.
  • You can display descriptions, specifications and nested subschema structure directly in the diagram.
  • Navigation and expand/collapse with keyboard arrows.
  • LIGHT and DARK themes available.
  • Zoom in, zoom out and reset UI zoom.
Display modes in Perseid Modeler for JSON schema and OpenAPI schema design
Import and visualization of JSON schema or OpenAPI

Import schema from a file

  • Visualization of both JSON schema and OpenAPI structures.
  • The import recognizes the contents of the file and creates the correct project type automatically.
  • Support for different versions or drafts of JSON schema and OpenAPI.

Find and navigate

  • Search in object names, but also in descriptions and specifications.
  • Search also in items that are collapsed.
  • Easy transition to the next search occurrence.
Find on tree diagram
JSON schema generated script

JSON schema & OpenAPI script generation

  • Generate JSON schema scripts for a single model or project
  • Edit properties in side panel or in modals
  • Generate strict JSON
  • Generate YAML or JSON code

Key benefits

A picture is worth a thousand words.

Blueprint to your own product: A diagram can give you a clear model of your data structure and help you recognize errors. It's like a blueprint to your house. You know what you are building, how to connect the pieces and you have the necessary documentation.

Efficient communication: It allows all your team members or clients to understand the relations JSON schema or OpenAPI structure in an effective manner.

Faster development: Draw JSON schema or OpenAPI structures and generate code. Avoid typos, make changes quickly.

Download Perseid Modeler
Trial/Early Access version expires 14 days after installation.

Windows OS
Windows Installer

Version: 1.2.5
File size: 70MB
Tested on: Windows 10 Pro

Linux AppImage

Version: 1.2.5
File size: 93MB
Tested on: Ubuntu 22.04
Get it from Snap Store

Windows OS
DMG file for MacOS

Version: 1.2.5
File size: 95MB
Tested on: MacBook Air & M1
Purchase Perseid Modeler

Perpertual license with 12 months free updates included.
User-based licensing model. One license key can be used on Windows, Linux and MacOS.

Single user license

199,- USD
Go to purchase page

EDU license

99,- USD
Request EDU License

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