Database Designer - Visual ERD Tool

Free online database designer and ERD (Entity Relationship Diagram) tool. Design database schemas visually, create tables, define relationships, and export to SQL. All data is saved in your browser - no signup required.

What is a Database Designer?

A database designer is a visual tool that helps you plan and model database structures before implementation. It allows you to create tables, define columns with data types, set primary keys, establish foreign key relationships, and visualize how your data entities connect to each other.

How to Use This Database Designer

1. Click "+ Table" to add a new table to your canvas
2. Drag tables to arrange them visually on the canvas
3. Click on a table to edit its columns in the sidebar
4. Add columns with appropriate data types (INT, VARCHAR, TEXT, etc.)
5. Mark primary keys and set NOT NULL constraints
6. Create foreign key relationships by selecting columns
7. Export to SQL to generate CREATE TABLE statements
8. Share your diagram using the shareable code feature

Supported Data Types

INT, BIGINT, SMALLINT, VARCHAR, TEXT, CHAR, BOOLEAN, DATE, DATETIME, TIMESTAMP, DECIMAL, FLOAT, DOUBLE, JSON, BLOB, ENUM

Key Features

• Visual drag-and-drop interface for table positioning
• Real-time foreign key relationship visualization
• Multiple project support with localStorage
• Auto-save functionality
• Export to SQL (CREATE TABLE and ALTER TABLE statements)
• Export to JSON for schema backup
• Shareable codes to transfer diagrams between users
• Primary key and NOT NULL constraint support
• No registration or backend required - 100% browser-based

When Should I Use a Database Designer?

• Planning a new application's database structure
• Documenting existing database schemas
• Collaborating with team members on data modeling
• Learning database design and normalization
• Prototyping before writing SQL
• Creating database documentation for projects

How to Share Your Database Diagram

Click "Export" and select "Generate Shareable Code". Copy the generated code and send it to anyone. They can paste it in the "Import" dialog to load your exact database design.

Is My Data Safe?

Yes! All your database designs are saved locally in your browser's localStorage. Nothing is sent to any server. Your data never leaves your device unless you explicitly export or share it.

Database Design Best Practices

• Use meaningful table and column names (users, products, order_id)
• Always define a primary key for each table
• Use foreign keys to maintain referential integrity
• Choose appropriate data types (don't use VARCHAR for numbers)
• Normalize your schema to reduce redundancy (3NF)
• Use NOT NULL constraints where appropriate
• Consider indexing columns used in WHERE clauses

Common Use Cases

E-commerce Database: Design tables for products, categories, customers, orders, and order_items with proper relationships.

Social Media Schema: Create tables for users, posts, comments, likes, and followers with many-to-many relationships.

Blog Database: Model tables for authors, posts, categories, tags, and comments.

CRM System: Design customer, company, contact, deal, and activity tables.

Alternative to Paid Tools

This free database designer is an alternative to expensive tools like MySQL Workbench, dbdiagram.io (paid features), Lucidchart, Draw.io, and ER/Studio. It runs entirely in your browser with no installation required.

SQL Export Example

CREATE TABLE users ( id INT PRIMARY KEY AUTO_INCREMENT, email VARCHAR(255) NOT NULL, created_at TIMESTAMP ); CREATE TABLE posts ( id INT PRIMARY KEY AUTO_INCREMENT, user_id INT NOT NULL, title VARCHAR(255), content TEXT ); ALTER TABLE posts ADD FOREIGN KEY (user_id) REFERENCES users(id);