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April 2026 — 6 min read

Free Online Database Designer — Visual Schema Builder for MySQL & PostgreSQL

A database designer is a tool for planning and visualising a relational database schema before you build it. Instead of writing CREATE TABLE statements from scratch, you work on a visual canvas — adding tables, defining columns, and drawing relationships between them. This guide explains what to look for in a free online database designer and how to get started.

What Does a Database Designer Do?

A database designer lets you model a relational schema graphically. The core workflow is:

• Add tables to a canvas, one per entity in your data model
• Define columns — name, data type, constraints
• Draw foreign key relationships between tables
• Export the schema as a SQL CREATE TABLE script

The visual canvas gives you a bird's-eye view of your entire schema. You can see at a glance how tables relate to each other, spot missing relationships, and reason about the structure without reading through walls of SQL.

Who Uses an Online Database Designer?

A free online database designer is useful across a wide range of roles and situations:

• Backend developers planning a new service or feature that requires database tables
• Students learning relational modelling and entity-relationship diagrams
• DBAs documenting an existing schema or exploring a redesign
• Freelancers who need to design a client database quickly without installing heavy tools
• Teams reviewing a schema design together — a visual diagram is far easier to discuss than DDL text

Free vs. Paid Database Designer Tools

Many popular database designer tools limit key features behind a paid plan. Common restrictions include:

• SQL export locked to paid tiers
• Limited number of tables per diagram on free accounts
• Private diagrams requiring a subscription
• Diagram count limits

SQL Designer has none of these restrictions. It's completely free — unlimited diagrams, unlimited tables, full SQL export — with no credit card or subscription required.

What to Look for in a Free Database Designer

• Support for your database — MySQL and PostgreSQL type systems are different; the tool should know which types are valid for each
• Full constraint support — PRIMARY KEY, UNIQUE, NOT NULL, auto-increment
• Visual foreign key lines — draw relationships between tables instead of writing constraint clauses
• ERD notation — crow's foot notation shows the cardinality of each relationship (one-to-many, etc.)
• SQL export — generate a valid CREATE TABLE DDL script directly from the diagram
• Runs in the browser — no install, available from any machine
• Auto-save — your work is saved automatically without a manual save step

SQL Designer — Free Online Database Designer

SQL Designer is a free online database designer for MySQL and PostgreSQL. It has a drag-and-drop canvas where you add tables, define columns with the correct type for your target database, set constraints, and draw foreign key relationships. When your design is complete, you export a clean CREATE TABLE SQL script for MySQL or PostgreSQL.

Everything runs in your browser — there's nothing to install. Create a free account with your email and you can start designing immediately. All diagrams are saved to your account and accessible from any device.

How to Design a Database with SQL Designer

• 1. Create a diagram — sign up for free and start a new diagram. Give it a name that reflects the database or service you're designing.
• 2. Add tables — add one table per entity. Common starting points: users, products, orders.
• 3. Define columns — for each column, set the name, data type (MySQL or PostgreSQL), and constraints (PK, UQ, NN).
• 4. Draw relationships — drag a line from the foreign key column to the primary key it references. The crow's foot notation is drawn automatically.
• 5. Export SQL — click the export button to download a complete, valid CREATE TABLE script for your chosen database.

Not sure if you want to sign up? The demo loads a sample schema so you can try the designer without creating an account.

Database Designer vs. Generic Diagram Tool

Tools like draw.io and Figma can produce a diagram that looks like a database schema. But they're generic — they don't know what VARCHAR(255) means, they can't validate that a foreign key points to a primary key, and they can't generate SQL. They're useful for high-level conceptual models, not for designing schemas you'll actually implement.

A purpose-built database designer keeps the visual model and the SQL in sync. The diagram is the schema — not a picture of the schema.