It depends on whether you are designing a new schema or documenting an existing one. To sketch a design quickly in text, dbdiagram.io (DBML) is freemium and browser-based; Mermaid is free and renders in GitHub Markdown. To reverse-engineer an existing database into a diagram, ChartDB is open source and self-hostable, and the database client you already use may be enough: DBeaver, DataGrip and dbForge Studio all generate diagrams from live schemas. For PostgreSQL-specific modelling, pgModeler is the specialist. For conceptual, logical and physical modelling with forward and reverse engineering across engines, look at Navicat Data Modeler, DbSchema or Redgate Data Modeler (formerly Vertabelo), and at erwin Data Modeler or ER/Studio for enterprise modelling on Windows.
An ER diagram tool earns its place in one of two jobs. Design: you draw entities and relationships before the database exists, then generate DDL (forward engineering). Documentation: you point the tool at an existing database and it draws what is there (reverse engineering), ideally keeping the diagram current as the schema changes. Some tools do both; many do one well.
The tools fall into four groups: browser-based modellers (dbdiagram.io, DrawSQL, ChartDB, Redgate Data Modeler), desktop modelling tools (Navicat Data Modeler, DbSchema, pgModeler, erwin Data Modeler, ER/Studio), the ER features inside database clients (DBeaver, DataGrip, dbForge Studio, the VS Code MSSQL extension), and diagram-as-code languages (Mermaid, PlantUML). If you are new to modelling, our SQL joins guide shows how the relationships in a diagram turn into queries.
Two status changes to know about. Redgate acquired Vertabelo in September 2025 and relaunched it as Redgate Data Modeler; the old Vertabelo pricing address now redirects to Redgate. And Oracle rebuilt MySQL Workbench as version 26 in July 2026: the current product page lists development, administration, performance and backup and migration, but does not mention EER modelling, although the download page still lists "Database Design & Modeling". Until Oracle's documentation agrees, we do not recommend relying on MySQL Workbench 26 for modelling, and earlier Workbench releases are end of life.
Quick picks
Write the schema in DBML and get a diagram; an open source CLI converts between DBML and SQL.
AGPL-licensed, runs in Docker, and imports a schema from the output of one query rather than a stored password.
Purpose-built for PostgreSQL objects, with reverse engineering, validation and a CLI; GPLv3 Community edition.
Plain-text ER diagrams that live beside your code; GitHub renders Mermaid in Markdown.
Conceptual, logical and physical models for eight engines on Windows, macOS and Linux, with a free Lite edition.
How we chose
Considered: dbdiagram.io, DrawSQL, ChartDB, Redgate Data Modeler (Vertabelo), ER/Studio, erwin Data Modeler, pgModeler, DbSchema, Navicat Data Modeler, Toad Data Modeler, DBeaver, DataGrip, dbForge Studio, SSMS database diagrams, the VS Code MSSQL extension's schema designer, MySQL Workbench, Mermaid and PlantUML.
Inclusion criteria: currently maintained; draws relational ER diagrams with tables, columns and relationships; supports at least one of forward engineering, reverse engineering or text-based definition; and its pricing model, platforms and supported databases could be confirmed on official pages. MySQL Workbench is not listed as an entry because its modelling status in version 26 is unclear. Toad Data Modeler is not listed separately because we could not confirm a current standalone release; Quest includes it in higher Toad for SQL Server editions. SSMS database diagrams are covered in the FAQ.
What was checked, not tested: product, pricing and documentation pages, GitHub repositories and release notes, on 7 October 2026. The order is not a ranking: browser tools first, then desktop modelling tools, then database clients, then diagram-as-code.
At a glance
| Tool | Price | Platforms | Databases | Design or document | Main trade-off |
|---|---|---|---|---|---|
| dbdiagram.io | Freemium | Browser | DBML; SQL for PostgreSQL, MySQL, SQL Server, Oracle via CLI | Design (text-first) | Free plan limited; diagrams are not a live model |
| DrawSQL | Freemium | Browser | MySQL, PostgreSQL, SQL Server, MariaDB | Design, collaboration | Imports SQL, no live database connection listed |
| ChartDB | Freemium (AGPL open source) | Browser, self-hosted (Docker) | PostgreSQL, MySQL, SQL Server, MariaDB, SQLite, ClickHouse, CockroachDB | Document, then design | Hosted free plan very small |
| Redgate Data Modeler | Paid (14-day trial) | Browser | Ten engines incl. SQL Server, Oracle, PostgreSQL, MySQL | Design, logical and physical (Pro) | Subscription only; Standard edition capped |
| Navicat Data Modeler | Paid (free Lite) | Windows, macOS, Linux | Eight engines incl. MongoDB, Snowflake | Both; conceptual to physical | Paid for full features |
| DbSchema | Freemium | Windows, macOS, Linux | Relational and NoSQL | Both | Model files, docs and design-first in paid editions |
| pgModeler | Freemium (GPLv3) | Windows, macOS, Linux | PostgreSQL | Both | PostgreSQL only; diff and sync in Plus |
| erwin Data Modeler | Paid | Windows | Many enterprise engines | Both, enterprise governance | Windows only; quote-based |
| ER/Studio | Paid | Windows (64-bit) | Many enterprise engines | Both, enterprise governance | Windows only; quote-based |
| DBeaver | Freemium | Windows, macOS, Linux | Many | Document (view free) | ERD edit mode and SVG export paid |
| DataGrip | Paid (free non-commercial) | Windows, macOS, Linux | Many | Document | No schema editing from diagrams documented |
| dbForge Studio | Freemium | Windows | SQL Server (and per-engine Studios) | Both, on a live database | Windows-native only |
| VS Code + MSSQL | Free | Windows, macOS, Linux | SQL Server, Azure SQL, Fabric SQL | Design and document | SQL Server family only |
| Mermaid and PlantUML | Free (open source) | Any (text) | Engine-neutral | Document in text | No database connection or DDL |
dbdiagram.io
dbdiagram.io is Holistics' browser tool for drawing ER diagrams by writing code in DBML (Database Markup Language), an open source, database-agnostic schema language that Holistics created and maintains. Its pricing page lists Free, Personal Pro, Team and Custom plans; the Free plan includes SQL import and export, up to 10 diagrams, and PNG, PDF and SVG export, while paid plans add private diagrams, version history and team workspaces.
The open source DBML CLI (npm install -g @dbml/cli) converts DBML to SQL for PostgreSQL, MySQL, SQL Server and Oracle, parses SQL into DBML, and can generate DBML from a live PostgreSQL, MySQL, SQL Server, Snowflake, BigQuery or Oracle database. Holistics also offers dbdocs.io for publishing schema documentation from DBML.
- The Free plan caps the number of diagrams, and private diagrams need a paid plan.
- The diagram is a design document; keeping it in step with a live database needs the CLI or manual updates.
DrawSQL
DrawSQL is a collaborative, browser-based schema diagram tool for MySQL, PostgreSQL, SQL Server and MariaDB. You import existing schemas by pasting CREATE TABLE statements, and export DDL for MySQL, PostgreSQL or SQL Server, Laravel migrations, JSON or PNG. Teams can comment on specific tables and edit a diagram together in real time on paid plans.
The pricing page lists a Free plan (unlimited public diagrams of up to 15 tables, 1 user) and paid Starter, Growth, Large and Enterprise plans, billed monthly or yearly, with limits on private diagrams, tables per diagram and users.
- Its site describes importing SQL, not connecting to a live database for reverse engineering.
- Free diagrams are public and limited to 15 tables.
- Supports four engines only.
ChartDB
ChartDB is an open source (AGPL-3.0), web-based diagram editor. Instead of connecting to your database, it gives you a single query to run; you paste the JSON result and it draws the schema. It supports PostgreSQL (including Supabase and Timescale), MySQL, SQL Server, MariaDB, SQLite (including Cloudflare D1), CockroachDB and ClickHouse. The latest GitHub release when we checked was v1.20.1 (7 April 2026).
You can self-host it with the published Docker image; its AI-assisted DDL export for migrating between dialects needs an OpenAI API key or a compatible inference server. The hosted service lists a Free plan (1 user, 1 database, up to 10 tables) and paid Pro, Teams and Custom plans that raise those limits and add a DBML editor, collaboration and versioning.
- The hosted Free plan is limited to 10 tables, so for real schemas you self-host or pay.
- AGPL-3.0 obligations apply if you modify it and offer it to others over a network.
- AI export features depend on a third-party model provider and key.
Redgate Data Modeler
Redgate Data Modeler is the former Vertabelo Data Modeler. Redgate acquired Vertabelo on 17 September 2025 and launched the product under its own name on 7 October 2025. Redgate describes it as a SaaS modelling tool with real-time collaboration and built-in versioning, and states that it supports ten database types, including SQL Server, Oracle, PostgreSQL and MySQL.
Redgate lists two editions, sold per user per year with a 14-day free trial: Standard (physical design, up to 20 models and 100 tables per model) and Pro (unlimited models and tables, logical design, API access and SSO). Pro is also included in Redgate's SQL Toolbelt Essentials bundle.
- No free plan; subscription only after the trial.
- Standard caps models and tables, and logical design is Pro-only.
- Browser-only, so your schema design lives in Redgate's cloud service.
DbSchema
DbSchema (version 10.5.2 on the download page) is a diagram-centred database design and management tool for relational and NoSQL databases. It comes in three editions: Community (free), Pro and Architect. The Community edition connects to databases, reverse-engineers them into interactive diagrams, lets you create tables and columns, and includes a SQL editor with autocompletion.
According to DbSchema's purchase page, offline model files, documentation generation and data tools are not in Community; Architect adds modelling before a database exists. Licences are per developer, perpetual with paid maintenance after the first year or monthly, and every download starts with a 15-day trial of all features.
- Offline model files and HTML documentation, two common reasons to use a modeller, are paid features.
- Design-first modelling needs the more expensive Architect edition.
pgModeler
pgModeler is a PostgreSQL-only modelling tool that covers more than 30 PostgreSQL object types, reverse-engineers live databases, validates models with automatic fixes, exports to SQL, PNG, SVG and HTML, and has a command-line interface for CI. It stores models in an XML format the project describes as suited to Git. The stable release is 1.2.3 (6 February 2026), with 2.0.0-beta1 published on 14 September 2026.
The Community edition is GPLv3 and free. The paid pgModeler Plus adds incremental diff and sync against live servers, a built-in database management module and SSH tunnelling, sold as time-limited or perpetual licences.
- PostgreSQL only.
- Comparing a model with a live server and syncing changes needs the paid Plus edition.
- Version 2.0 is still in beta.
erwin Data Modeler
erwin Data Modeler, owned by Quest Software, is a long-established enterprise modelling tool. Quest's support site lists documentation for release 15.2. The release notes describe a Standard edition (all modelling features, standalone) and a Workgroup edition that adds multi-user modelling with conflict resolution, versioning and security through a shared model mart.
The release 15.0 system requirements list 64-bit Windows 11, with optional support for Windows Server 2016 to 2025, and 16 GB of RAM. Quest sells it through sales and trials rather than published prices.
- Windows only.
- Prices are not published; expect an enterprise sales process.
- In our view it is more than a developer needs for a single application schema.
ER/Studio
ER/Studio, owned by Idera, is an enterprise data modelling platform combining logical and physical modelling, with governance integrations. It is sold as Data Architect (individual, local data dictionary), Data Architect Pro (adds a central repository and team collaboration) and Enterprise (adds Team Server Core and governance integrations). Idera lists support for SQL Server, Oracle, PostgreSQL, Snowflake, Databricks, Microsoft Fabric, MongoDB, BigQuery, Redshift and others.
The technical specifications for ER/Studio Data Architect 21.1.x list 64-bit Windows 11 and Windows 10. Prices are not shown publicly; a free trial is offered.
- Windows only.
- Quote-based pricing; team features need the Pro or Enterprise tiers.
DBeaver
DBeaver generates ER diagrams for a table, a whole schema or a custom set of objects, with auto-layout, search, zoom and an outline view. In Community you can export diagrams as PNG, GIF, BMP or GraphML. SVG export is marked as PRO-only, and editing the schema from the diagram (ERD edit mode) needs a paid edition.
- Free use is mainly for viewing and documenting existing schemas; designing through the diagram needs a paid edition.
- No conceptual or logical modelling layer.
DataGrip
DataGrip generates diagrams for a data source, a schema or a table, showing primary and foreign key relationships, with optional column comments and colours. Its export options are useful for documentation: PNG, Mermaid, PlantUML, Graphviz DOT, yEd GraphML and draw.io, plus direct export to web editors such as Mermaid Live and diagrams.net.
- JetBrains' diagram documentation does not describe changing the schema from the diagram.
- Commercial use requires a subscription.
dbForge Studio
dbForge Studio for SQL Server includes a Database Designer: you drag objects from Database Explorer onto a diagram, then create or change relationships, columns, indexes, keys, constraints and triggers from it. Diagram containers group related tables in large schemas, and diagrams export as BMP, JPG, GIF, PNG, TIFF or EMF. Database diagrams are listed in the free Express edition. Devart publishes separate Studios for MySQL and MariaDB, Oracle and PostgreSQL.
- Windows-native only.
- It works on a live database rather than as a separate, versioned model.
- No vector (SVG) or text export format is listed for diagrams.
VS Code with the MSSQL extension
Microsoft's MSSQL extension for Visual Studio Code includes a schema designer, marked generally available, for visual schema modelling with drag-and-drop and auto-layout, plus a table designer that generates T-SQL and publishes changes. A Copilot-assisted schema designer for natural-language design is also listed as GA. It runs on Windows, macOS and Linux.
On Windows, SSMS also has database diagrams and table designers; the extension is the cross-platform route for the same family of databases.
- SQL Server, Azure SQL and SQL database in Fabric only.
- No separate conceptual or logical model.
Read our VS Code with the MSSQL extension review · Official site
Mermaid and PlantUML
Mermaid (MIT licence) has an erDiagram type that uses crow's foot notation, marks attributes as PK, FK or UK, and distinguishes identifying from non-identifying relationships. GitHub renders Mermaid diagrams in Markdown files, issues, pull requests, discussions and wikis, so a schema diagram can sit in the repository next to the migrations.
PlantUML (v1.2026.8, offered under several licences including GPL, Apache 2.0 and MIT) supports Information Engineering ER diagrams with an entity keyword and crow's foot relations. DataGrip can export database diagrams to both formats, which is a quick way to seed a diagram-as-code file from a real schema.
- Neither connects to a database or generates DDL; the diagram can drift from the real schema unless you regenerate it.
- Layout is automatic, so large schemas can be hard to read.
How to choose
Documenting an existing database: start with the client you already have (DBeaver, DataGrip, dbForge Studio or SSMS on Windows). If you need something shareable without a desktop tool, ChartDB or DbSchema reverse-engineer a schema into a diagram; DataGrip and the DBML CLI can turn it into text you can commit.
Designing a new schema: dbdiagram.io or DrawSQL for quick, collaborative sketches that generate DDL; pgModeler if the target is PostgreSQL; Navicat Data Modeler, DbSchema Architect or Redgate Data Modeler when you want separate logical and physical models. Enterprise modelling and governance: erwin Data Modeler or ER/Studio, both Windows desktop products sold through sales.
When none of these is needed: for a handful of tables, a Mermaid block in your README is often enough. Whatever you pick, a diagram is only as good as its last update, so prefer tools that can regenerate from the live database. To practise the queries those relationships make possible, try our SQL exercises.
Frequently asked questions
What is the best free ER diagram tool?
It depends on the job. For drawing from text, Mermaid is free and open source and dbdiagram.io has a free plan. For diagrams of an existing database, DBeaver Community, ChartDB (self-hosted) and the DbSchema Community edition are free. For PostgreSQL, the pgModeler Community edition is free under GPLv3.
Can I generate an ER diagram from an existing database?
Yes. DBeaver, DataGrip, dbForge Studio, DbSchema, Navicat Data Modeler, pgModeler, erwin and ER/Studio reverse-engineer live databases. ChartDB uses the output of a query you run yourself, and the DBML CLI can generate DBML from a live database for dbdiagram.io.
Does SSMS have ER diagrams?
SSMS has database diagrams and table designers, and Microsoft lists them among the reasons to use SSMS. They work on SQL Server databases on Windows only. For a cross-platform option, the MSSQL extension for VS Code has a schema designer.
Does MySQL Workbench still do EER modelling?
It is unclear. MySQL Workbench 26 (July 2026) is a rebuild, and its product page does not mention EER modelling, while the download page still lists database design and modelling. Earlier Workbench releases are end of life. Check Oracle's current release notes before relying on it.
What happened to Vertabelo?
Redgate acquired Vertabelo in September 2025 and relaunched its modeller as Redgate Data Modeler in October 2025. It remains browser-based and is sold per user per year in Standard and Pro editions.
Sources
- dbdiagram.io pricing
- DBML documentation and CLI
- DrawSQL pricing
- ChartDB GitHub repository
- ChartDB pricing
- Redgate Data Modeler editions
- Redgate launches Redgate Data Modeler after acquiring Vertabelo (press release)
- Navicat Data Modeler product page
- DbSchema purchase and editions
- pgModeler
- erwin Data Modeler 15.0 system requirements (Quest)
- ER/Studio (Idera)
- ER/Studio Data Architect technical specifications
- DBeaver ER diagrams documentation
- DataGrip diagrams documentation
- dbForge Studio for SQL Server: create a database diagram (Devart docs)
- MSSQL extension for Visual Studio Code (Microsoft Learn)
- MySQL Workbench product page (Oracle)
- Mermaid entity relationship diagrams
- Creating diagrams on GitHub (GitHub Docs)
- PlantUML Information Engineering diagrams
Checked October 2026.
How we research these guides: our editorial method.