Frequently Asked Questions

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, SQLite, 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:

• macOS - Apple Silicon (arm64) and Intel (x64)
• Windows - Windows 10/11 x64
• Linux - Ubuntu and Debian (.deb)

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 [email protected] with your .edu address to request a free education license.

ChartDB is a cloud schema visualizer - collaboration, AI, and storage all live on the web. Schemity is the offline desktop alternative: your diagrams are plain JSON files on your own machine, AI assistance is bring-your-own-key (or fully local via Ollama), migrations are generated as reviewable SQL, and the license is a one-time purchase instead of a subscription. Read the full comparison in Schemity vs ChartDB.

dbdiagram.io is a cloud tool where you describe the schema in a DSL (DBML) and pay a subscription. Schemity is a visual-first desktop ERD tool: you design directly on the canvas, work fully offline, keep diagrams as local JSON files under Git, and buy it once. Read the full comparison in Schemity vs dbdiagram.io.

Yes. Schemity imports DBML, so a schema from dbdiagram.io or any DBML-based tool moves over in one step - entities and relationships are generated automatically. It also exports DBML, so your schema stays portable in the other direction too. See why switching ERD tools shouldn't mean starting over.

Schemity Lite is the free, online version of Schemity that runs in your browser at lite.schemity.com. It's built for quick visual schema design and one-link online sharing - no install, no account, no credit card. It uses a single default workspace and does not include the desktop-only features such as database connections, reverse engineering, migration generation, SSH tunneling, custom workspaces, or offline use. For those, get the desktop License.

Lite is the online browser version of Schemity - always free, but limited to schema design and online sharing. The Trial is the full desktop app with every feature unlocked for 2 weeks, so you can evaluate database connections, migrations, custom workspaces, and offline work before buying. Use Lite for fast, shareable diagrams; use the Trial to test the complete tool.

After the trial expires, the desktop app keeps working with a feature set close to Lite's - visual schema design without the licensed features - but with the nature of a desktop app rather than an online one: it works offline, your diagrams stay plain local JSON files, and there is no online sharing link.

In Schemity Lite, once you're signed in, you can turn any diagram into a public link. Anyone with the link can view your ERD in their browser - no account needed to look. You can also export the diagram as PNG, JPEG, SVG, SQL, Mermaid, DBML, or JSON - for docs and presentations, to build the database, to render the ERD in markdown, or to keep it in Git.

No - Lite is for visual schema design and sharing. To connect to live databases (MySQL, PostgreSQL, SQL Server, and more), reverse-engineer existing schemas, and generate SQL migrations, use the Schemity desktop app. It's an offline ERD tool that keeps your schema on your machine.

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.

No. Schemity works as a standalone database design tool: design from scratch on the canvas, or import a SQL dump or DBML file to generate the diagram without touching a live database. A connection is only needed when you want to reverse-engineer a running database or apply generated migrations to it.

Yes. Schemity supports reverse engineering - reverse engineer PostgreSQL to ERD, visualize a MySQL schema on your desktop, or connect to MariaDB, SQL Server, SQLite, 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.

Yes. For a reverse-engineered diagram, the live database is the source of truth: reopening the diagram automatically pulls the latest schema, and a Reset ERD action does the same on demand. Existing entities keep their layout, dropped tables disappear, and new tables appear ready to drag into place. See re-sync for details.

Context views are focused sub-diagrams of your main ERD. You pull in just the entities for one subject area - auth, billing, analytics - and arrange them freely, while the main view stays the single source of truth. An orange dot marks any entity with relationships outside the view, so a focused diagram never hides that it is incomplete. You can create as many database context views as you need. See the context views documentation.

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.

You can export any diagram or context view as a JPG, PNG, or SVG image, export the full SQL of the main view or any context view (or a single entity or legend), and export the schema as DBML for dbdiagram.io, dbdocs, and the wider DBML toolchain. Exports work fully offline.

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. Lines turn with smooth rounded corners at their waypoints, and where two lines cross, one hops over the other with a small arc - on the canvas and in SVG export - so you can always tell which line goes where.

Schemity supports full constraint coverage including:

• Unique
• Not null
• Default values
• ERD check constraints support (which also act as living documentation)
• ERD composite unique constraints
• Indexes

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:

• Vim-style canvas navigation (h j k l)
• Hot keys for all common operations
• Tab navigation with Cmd+1 through Cmd+9

Yes. 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.

An entity template is a reusable starting point for new tables. You define a set of fields you add to almost every entity - say id, created_at, and updated_at - and save it as a template. You can create multiple templates and mark one as active. Whenever you create a new entity, it's pre-populated with all the fields from the active template, so you stop retyping the same columns on every table. It's available in all versions, including Lite.

BYOK means "bring your own key". You add your own AI provider API key and chat with an assistant that understands your schema - ask it to explain a design, suggest tables and relationships, or refine your model. Because the requests go directly from Schemity to the provider using your key, there's no Schemity-hosted AI server in the middle and no extra AI subscription. Supported providers are OpenAI, Gemini, Claude, Grok, and DeepSeek - and you can also add Ollama with a configurable base URL to chat with local models running on your own machine, so nothing leaves it at all. The AI assistant is available on the desktop License; it isn't included in the Lite version.

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.

Yes. All design work - the canvas, reverse engineering, migrations, exports, JSON storage - runs entirely on your machine with no network dependency, so Schemity works as an air-gapped ERD tool behind strict no-egress policies. Even AI assistance can stay local: add Ollama as a provider and chat with models running on your own hardware, with zero data leaving the machine.

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.

Yes, and the workflow is built for exactly that caution: connections go through an SSH tunnel, passwords live in the OS keychain, connections are tagged by environment (Local, Staging, Production), and reverse engineering only reads the schema. Nothing is ever written unless you explicitly review and apply a generated migration diff. See documenting production shouldn't feel dangerous.

Schemity is a one-time purchase ERD tool 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 with a feature set close to Lite's - visual schema design continues to work offline, just without the licensed features such as database connections and migrations. 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.

A Schemity license is tied to the machine ID of the device you activate it on. If you replace your machine or need to move the license, contact [email protected] and the transfer will be sorted out.

The license is tied to your machine ID. Contact [email protected] for assistance with license transfers.

Yes. Schemity is free for students and educators with all features unlocked and 1 year of updates included. Email [email protected] with your .edu email address to request a free license.

The app works forever - you just stop receiving new feature updates. Security patches are always free regardless of your update status. You can renew at any time to get the latest features.

All payments are processed by LemonSqueezy, which accepts credit cards, debit cards, and PayPal. Schemity never sees or stores your payment information.

Get in touch and it will be worked out with you directly. The checkout on this site covers a single license paid by card or PayPal, so anything beyond that - licensing a whole team at once, paying by invoice or purchase order, activating on machines with no internet access, or answering a security review - is handled by email rather than automated on the site.

Email [email protected] with what you need, or see Buying Schemity for a team on the pricing page. Schemity stays a one-time purchase either way - there is no per-seat subscription tier and no features held back behind an enterprise plan. What gets discussed is volume and paperwork, not what the app can do.

Use the GitHub feedback repository to report bugs and submit feature requests. You can also reach out on the Discord community.

Email us at [email protected] 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.