A free alternative to erwin Data Modeler
erwin Data Modeler (from Quest) is one of the longest-established enterprise data modeling suites. EntityModel.com covers the core erwin workflow (logical and physical models, forward and reverse engineering, compare, standards and documentation) in a free, open-source tool that runs in the browser.
Comparison as of November 2026. erwin is sold by subscription in several editions; contact Quest for current editions and pricing.
At a glance
| EntityModel.com | erwin Data Modeler | |
|---|---|---|
| License and price | Open source (MIT), free | Commercial, subscription |
| Install | None: runs in the browser, works offline, optional local mode | Desktop software (Windows) |
| Logical and physical models | Yes: tabs of one model, derived from each other with lineage | Yes |
| Conceptual models | Yes | Yes |
| Reverse engineering | SQL/DBML scripts; Databricks, Snowflake, PostgreSQL, MySQL schemas | Wide range of databases |
| Forward engineering | PostgreSQL, MySQL/MariaDB, Snowflake, Databricks DDL; DBML, Mermaid | Wide range of databases |
| Compare and migration scripts | Compare any two tabs; ALTER/CREATE/DROP with renames |
Yes |
| Naming standards | Per model kind, with automatic fixes | Yes |
| Reports and documentation | PDF design document, data dictionary tables (Google Docs, Word, Confluence, Markdown) | Yes |
| Model sharing | Model file, share links, Git with pull request review | Central model repository (in some editions) |
| dbt, data contracts | dbt schema.yml, ODCS, JSON Schema, Avro |
Varies by edition and integrations |
| AI agents | MCP server and Claude skills; agents propose changes you review | Varies by version |
The erwin workflow in EntityModel.com
| In erwin | In EntityModel.com |
|---|---|
| Logical and physical model | A logical tab and a physical tab; New tab → Derive creates one from the other |
| Reverse engineer | Import SQL or DBML, or Import → From a database (guide) |
| Forward engineer | Export → Code → SQL DDL (guide) |
| Complete Compare | Compare two tabs, then Migration SQL or Sync from source (guide) |
| Naming standards | Model inspector → naming standards; Issues → Fix (guide) |
| Domains and valid values | Reference entities with their values (guide) |
| Subject areas | Areas on the canvas, and tabs for views of the model |
| Reports | Export → PDF document and the Tables view (guide) |
| Mart (repository) | Model files in Git, reviewed with em review in pull requests (guide) |
When erwin is the better choice
- You need a central model repository with check-in, check-out and permissions for a large modeling team.
- You target databases EntityModel.com doesn't generate DDL for, such as Oracle, SQL Server, Db2 or Teradata.
- You rely on erwin's integrations with a wider data governance suite.
When EntityModel.com is the better choice
- You want logical and physical modeling without license costs, installs or Windows.
- Your platforms are PostgreSQL, MySQL, Snowflake or Databricks, and your workflow includes dbt and Git.
- You want models as plain files that engineers, CI and AI agents can work with.
Frequently asked questions
Is there a free alternative to erwin Data Modeler?
Yes. EntityModel.com is a free, MIT-licensed data modeling tool that runs in the browser. It supports logical and physical models, reverse and forward engineering for PostgreSQL, MySQL, Snowflake and Databricks, model compare with migration SQL, naming standards and PDF design documents.
Can EntityModel.com open erwin models?
Not directly. Export the physical model from erwin as a SQL DDL script, then import the script into EntityModel.com; tables, keys, comments and foreign keys come across.