Everything you need to know about Schemity.
General
Schemity is an offline desktop ERD tool built for software engineers that turns complex databases into understandable systems. It lets you reverse-engineer a database, break it into focused Context Views (one main ERD as a single source of truth, plus read-only context views for auth, billing, analytics, etc.), and generate precise SQL migrations as your schema evolves - all without sending your data to any cloud server. It is a lightweight ERD tool that starts in seconds and runs fully offline. Your ERDs are stored as plain JSON files, making it a Git-native ERD tool by design.
Schemity supports MySQL, MariaDB, PostgreSQL, SQL Server, and Supabase. PostgreSQL users also get multi-schema support - not just the public schema. You can connect through direct or SSH connections.
Schemity is available as a native desktop app on:
Schemity offers a 2-week free trial with all features unlocked, no credit card required. After the trial, the app is still usable - your work is never held hostage.
Schemity is also free for students and educators. Email support@schemity.com with your .edu address to request a free education license.
Features
Use the visual ERD designer to drag and drop entities onto the canvas, define fields, and connect them with relationships. The interface supports auto-resize, snap-to-guide alignment, and smart connection lines. For speed, use entity templates to reuse common field patterns across entities.
Yes. Schemity supports reverse engineering - reverse engineer PostgreSQL to ERD, visualize a MySQL schema on your desktop, or connect to MariaDB, SQL Server, or Supabase and the ERD is generated automatically. This is useful for documenting legacy systems, visualizing a Supabase schema diagram, or onboarding to a new codebase.
Schemity compares your ERD design with the actual database state and generates the exact migration SQL diff to bring them in sync. It handles CREATE, ALTER, and DROP statements automatically. Every migration requires explicit confirmation before being applied, protecting you from accidental changes.
Schemity supports 1:N and N:N relationships with auto junction table generation. Relationship lines adapt and reroute automatically as you move entities on the canvas. You can also add ERD custom waypoints for full manual control over line routing.
Schemity supports full constraint coverage including:
Yes. Schemity supports secure SSH tunneling for connecting to remote databases. Your database credentials are stored safely in your operating system's native keyring - never in plaintext files.
Schemity is built for keyboard-first use. Every action has a shortcut. It supports:
h j k l)Cmd+1 through Cmd+9Yes. Schemity supports multiple native tabs with isolated undo history per ERD. You can switch between them quickly using number-key navigation, making it easy to work across multiple schemas or projects in a single session.
Yes. Schemity has full temporal state management with undo/redo history. Each tab maintains its own isolated history, so undoing in one ERD never affects another.
Yes. You can assign custom colors to entities and their relationships for instant visual grouping and clearer ERD readability.
Yes. Schemity is a Git-native ERD tool - your ERDs are plain JSON files stored locally. You can version control database diagrams in Git, review schema changes in pull requests, and maintain a full history of every design decision. This is a core part of how Schemity is designed to be used.
Privacy & Data
No. Schemity is a fully offline ERD tool with no cloud dependency. Your database schemas, designs, and all project data are stored locally on your machine and are never transmitted to any server. It works air-gapped, behind VPNs, and on locked-down corporate laptops - an ERD tool approved by IT because there is nothing to review.
Your workspace is stored as plain JSON files in a local folder on your machine. This ERD tool uses JSON storage by design, giving you complete data ownership with no cloud dependency. You can version control your database diagrams in Git, back up, move, or delete your data at any time. Safe for NDA projects and client work.
Schemity does not collect any personal information. The only data it transmits is an auto-generated machine ID and your country code, both used solely for license verification. When you purchase a license, your payment and email are handled entirely by LemonSqueezy - Schemity does not store any of that information.
Yes. Schemity does not store your database credentials on any remote server. All connection details, including SSH credentials, remain on your local machine and are stored in your OS native keyring.
License & Pricing
Schemity is a one-time purchase ERD tool at $129 with 1 year of updates included. After the first year, you can optionally renew updates for $69/year. Security patches are always free. An ERD tool without subscription - the app works forever even without renewing. You just stop receiving new feature updates.
There is also a free 2-week trial with all features unlocked, and a free education license for students and educators.
Your work is never held hostage. After the trial expires, Schemity stops receiving updates but remains usable. You get a single friendly reminder when you open the app, once per session - not a popup that blocks your work. Your ERD files are plain JSON on your machine and are always yours.
License activation is handled through LemonSqueezy. After purchase, you will receive a license key via email. Enter that key along with your email address inside Schemity to activate it on your device.
The license is tied to your machine ID. Contact support@schemity.com for assistance with license transfers.
Yes. Schemity is free for students and educators with all features unlocked and 1 year of updates included. Email support@schemity.com with your .edu email address to request a free license.
Support
Use the GitHub feedback repository to report bugs and submit feature requests. You can also reach out on the Discord community.
Email us at support@schemity.com for any questions, licensing issues, or general inquiries.
Yes! Join the Schemity Discord server to connect with other users, share feedback, and get updates on new releases.
New versions are released periodically. Download the latest installer from the Platforms section of the website and install it over your existing version.