Schemity turns complex schemas into understandable systems. Break a 50-table database into focused Context Views - one source of truth, many perspectives. Designed for engineers who need to reason about systems, not just draw tables.
PostgreSQL
Supabase
MySQL
MariaDB
SQL Server
Most ERD tools force one giant diagram and hope you can read it. Schemity lets you keep a single source of truth, then project it into Context Views - auth, billing, analytics, whatever lens you need. Multi-layer modeling (tabs for systems, schemas for structure, views for use cases), Git-native, fully offline, in a 9 MB native app.
Create foreign keys by dragging fields between entities - 1:N, 1:1, or N:N with auto-generated junction tables. Color-coded connection lines and smart routing keep complex diagrams readable.
Your ERD lives as a JSON file in your repo. Commit it, review it in PRs, let your team pull it. No cloud account, no shared workspace to manage.
Your main diagram is the single source of truth. Context Views are read-only projections that pull in just the entities for one concern - auth, billing, analytics. Design once, understand everywhere.
Compares your ERD to the live database and generates the exact SQL diff. Reverse-engineer an existing database into an ERD, evolve the design, then apply migrations directly.
Unique constraints, check constraints, indexes, and not-null rules are part of your visual design - not afterthoughts buried in migration files. Smart color indicators make multi-column constraints immediately visible.
Plain JSON files in ~/schemity/ - readable, backupable,
portable. You own your data completely. No cloud dependency.
Download in seconds, not minutes. No IT ticket, no JRE installation, no license wizard. Built with Native WebView and Rust. Works offline, behind VPN, air-gapped. macOS, Windows, and Linux.
Connect to MySQL, MariaDB, PostgreSQL, SQL Server, or Supabase through direct or SSH connections - or work in ERD-only mode when you just need to think through the schema.
Tabs for systems, schemas for structure, Context Views for use cases. Three layers of organization that mirror how engineers actually think about complex databases - not one flat canvas.
Smart defaults, drag-and-drop relationships, and a visual editor built for software engineers - so you can focus on your data model, not the tool.
Sketch your schema in seconds. Go from concept to concrete entities before the idea fades.
Create 1:N, 1:1, or N:N relationships with simple drag-and-drop. Auto-generated junction tables, auto FK naming - no manual wiring needed.
Arrange your diagram the way you think about it, not the way the layout forces you. Lines adapt and reroute automatically. Add custom waypoints for full control.
Encode business rules as constraints. They become both enforceable logic and living documentation - referenceable directly in default values.
Group related entities visually. Color-code entity groups and their relationship lines for instant clarity on large diagrams.
Instantly distinguish between single-field unique constraints and composite unique together groups at a glance.
Every schema change requires explicit migration confirmation - no accidental alterations to your database. Review the exact SQL diff before applying.
Use tabs to separate the systems you work on - one product, one tab. Quick number-key navigation keeps you focused as you move between domains.
Model across PostgreSQL schemas - not just the public schema. Use them to express domains and structural boundaries inside a single database.
A complete breakdown of what Schemity can do for you, by category.
Connect your database, break it into focused Context Views, and evolve the schema with confidence - all from a single source of truth.
Reverse-engineer a live database in seconds, or start from scratch. Schemity gives you a complete picture of your schema as a single source of truth.
Reduce 50 tables down to a 10-table focused view. Create one Context View per concern - auth, billing, analytics - so each part of the system becomes understandable on its own.
Schemity diffs your ERD against the live database and generates the exact SQL migration. Your ERD lives as plain JSON in your repo - commit, review in PRs, and let teammates pull.
Schemity is designed to collect as little as possible. What we don't store, we don't have to protect.
We only store an auto-generated device ID and your country - for license management and regional support. No name, no email, no usage tracking. Nothing that identifies you.
All payment processing and billing are managed by LemonSqueezy. Schemity never sees or stores your payment information.
Because Schemity stores almost nothing, it largely satisfies SOC 2 and ISO 27001 requirements by design. Your ERD files live locally in your repo - not on our servers.
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Experience seamless performance and native feel across all major operating systems.
9 MB download. Running in seconds. Connect your database, create your first Context View, and see the system clearly - in minutes, not months. Your diagrams live as JSON in your repo, always yours.