ERD Generator from SQL
100% LocalGenerate Entity-Relationship Diagrams directly from SQL DDL statements.
Privacy note
This tool runs entirely in your browser. Your input is never uploaded, logged, or sent to AllDevToolsHub or anyone else, and it keeps working offline once the page has loaded.
How to Use ERD Generator from SQL
Paste SQL Schema
Enter CREATE TABLE statements or SQL schema definitions.
Generate ERD
The tool parses table definitions, columns, and foreign keys to render an entity relationship diagram.
Export
Download the ERD as an image or SVG for documentation.
ERD Generator from SQL: the essentials
The ERD Generator from SQL parses CREATE TABLE statements (with foreign key constraints) and renders an interactive Entity-Relationship Diagram. Exports to SVG for documentation. Saves an afternoon of manual diagramming when you've inherited a database schema and need to understand the relationships.
Key points
- Processes SQL syntax and structure only, never connects to any database server.
- Handles common syntax differences between multiple SQL dialects.
- Production queries with schema details and embedded literals stay entirely in your browser.
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What is ERD Generator from SQL?
Frequently Asked Questions
Technical Deep Dive
ERD Generator from SQL
Paste your raw CREATE TABLE statements and foreign key constraints to instantly visualize an interactive Entity-Relationship Diagram (ERD). You can download the generated diagram as an SVG vector image for use in documentation.
SQL-Aware
Understands joins, indices, and query plans, not just text manipulation.
Schema-Faithful
Preserves constraints, foreign keys, and data types through every transformation.
Big-Table Ready
Handles realistic dataset sizes without locking the tab or eating your RAM.
01 Cardinality Notation Matrix (Crow's Foot)
| Visual Symbol | Relationship Type | SQL Representation |
|---|---|---|
| ─┤├─ | Exactly One (Required) | NOT NULL on foreign key |
| ─┤○ | Zero or One (Optional) | NULL allowed on foreign key |
| ─┤├< | One to Many (Required) | Standard REFERENCES target |
| >├┤─ | Many to Many | Join Table (materialized) |