Free Entity Relationship Diagram Maker

An entity-relationship diagram visualizes how database tables connect — showing entities, their attributes, and the relationships between them. Software engineers, data architects, and analysts use ERDs to design new schemas, document existing databases, and plan migrations. Describe your data model in plain English and AI builds the diagram for you.

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3 EASY STEPS

How it works

Create stunning flow charts in minutes with our AI-powered tool. Transform your ideas into visual masterpieces effortlessly.

01Describe Your Process

Input your ideas or upload a file describing your workflow or process.

02AI Generation

Our AI analyzes your input and creates a professional flow chart based on your description.

03Customize and Share

Fine-tune your flow chart, then export or share it with your team instantly.

Why Choose Us

Idea to Diagram

Write naturally. We handle the translation from your thoughts to visual diagrams. No more wrestling with drag-and-drop tools.

Import Anything

PDFs, docs, images, or code - drop any file. We'll extract the logic and create a diagram that makes sense.

Fast Iterative Updates

Quick iterations are the key to good diagrams. Tell us what to change, and see updates in seconds, not minutes.

Export Anywhere

Get your diagram in any format you need - PNG, SVG, PDF, or even editable files. No lock-in, just flexibility.

Frequently Asked Questions

What is an entity relationship diagram?01

An entity-relationship diagram (ERD) is a data modeling tool that visualizes how entities — like customers, orders, and products — connect to each other in a database. Each entity has attributes (columns), and lines between entities show relationships with cardinality rules (one-to-one, one-to-many, many-to-many).

What are the different types of ER diagrams?02

There are three levels: conceptual (high-level entities and relationships only), logical (adds attributes, primary keys, and data types), and physical (maps directly to database tables with SQL-ready column definitions). This tool generates logical-level ERDs by default, which is what most teams need for planning and documentation.

How does this entity relationship diagram maker work?03

Describe your data model in plain language — for example, 'each department has many employees, employees can work on multiple projects' — and the AI produces a complete entity-relationship diagram with attributes and cardinality. You can also paste SQL CREATE TABLE statements or ORM schemas.

Can I edit the generated ER diagram?04

Yes. After the diagram is generated, you can refine it by asking the AI to add entities, change relationship types, rename attributes, or adjust cardinality — all through natural language.

What makes a good prompt for generating an ERD?05

Be specific about entities, their key attributes, and how they relate. For example: 'A student enrolls in many courses. Each course is taught by one professor. Professors belong to a department. Include student ID, name, GPA as attributes.' The more context you give, the more accurate the diagram.

Who uses entity relationship diagrams and when?06

ER diagrams are used before building a database (schema design), when joining a team (understanding existing data), during migrations (planning structural changes), and in technical documentation. They're standard practice in software engineering, data science, and systems architecture.

Is this tool free to use?07

Yes, it is free with a free account. No credit card is needed. Describe your data model and get an entity-relationship diagram in seconds.

SEE IN ACTION

Real templates built with Free Entity Relationship Diagram Maker

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