Break complex schemas into focused Context Views - one source of truth, many perspectives. Your schema never leaves your machine. One-time purchase, no subscription.
No credit card required. 2-week full trial.
PostgreSQL
Supabase
MySQL
MariaDB
SQL Server
A schema visualizer with smart defaults, drag-and-drop relationships, and a visual editor that gets out of your way - so your team spends time understanding the schema, not fighting 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 junction table generation, auto FK naming - no manual wiring needed.
Arrange your ERD the way you think about it, not the way the layout forces you. Lines adapt and reroute automatically. Add ERD custom waypoints for full control.
Full check constraint support - write any expression you need. For IN constraints, Schemity extracts the allowed values into a selectable dropdown for default values - self-documenting and enforceable in one step.
Group related entities visually. Color-code entity groups and their relationship lines for instant clarity on large schemas.
Instantly distinguish between single-field unique constraints and ERD composite unique constraints at a glance.
Every schema change requires explicit migration confirmation - no accidental alterations to your database. Review the exact ERD migration 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.
Import CREATE TABLE statements or load a SQL dump file. Schemity builds entities, fields, and relationships automatically - no database connection needed.
AI ERD without cloud - full control from chat. Create entities, define relationships, edit or delete fields, and import entities into Context Views. BYOK - your data goes directly to your AI provider, never through our servers.
Most ERD tools force one giant ERD and hope you can read it. This local ERD tool lets you keep a single source of truth, then project it into Context Views - auth, billing, analytics, whatever perspective you need. Your client's schema never touches a third-party server. An ERD tool approved by IT that works on locked-down corporate laptops. Document production database schemas in minutes, not weeks.
Create foreign keys by dragging fields between entities - 1:N, 1:1, or N:N with auto junction table generation. Color-coded connection lines and smart routing keep complex schemas readable.
Your ERD lives as a JSON file in your repo - never on a third-party server. A Git-native ERD tool with JSON storage, safe for NDA projects and client work. Commit it, review it in PRs, version control your database diagram in Git.
Your main ERD is the single source of truth. Database context views are read-only focused views for each concern - auth, billing, analytics. Ready for audits, onboarding, or handovers without rebuilding from scratch.
Reverse engineer PostgreSQL, MySQL, or SQL Server into a visual ERD, then generate the exact migration SQL diff as you evolve the design. Turn weeks of audit preparation and handover documentation into minutes.
ERD check constraints support, composite unique 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. An ERD tool with no cloud dependency. Safe for
compliance-sensitive and NDA-covered projects.
A lightweight ERD tool with a small installer. No Electron, no JVM, no IT ticket needed. Works offline, behind VPN, air-gapped - runs anywhere your team does. 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.
Import CREATE TABLE statements or load a SQL dump and Schemity builds the full ERD - entities, fields, and relationships - automatically. No database connection required. Generate an ERD from SQL in seconds.
Private AI database design from a chat interface - create entities, define relationships, add or edit fields, and import entities into Context Views. BYOK (Bring Your Own Key) means your data flows directly to your AI provider with no intermediate server. An offline AI ERD tool that never stores or processes your data. Supports Claude, OpenAI, Google Gemini, DeepSeek, and Grok.
Tabs for systems, schemas for structure, Context Views as ERD perspectives for use cases. Three layers of data modeling that mirror how engineers actually think about complex databases - not one flat canvas.
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 PostgreSQL to ERD in seconds, visualize a MySQL schema on your desktop, or start from scratch. Get a complete visual picture of your schema - no weeks of manual documentation. Everything stays on your machine.
Reduce 50 tables down to a 10-table focused view. Create one Context View per concern - auth, billing, analytics - ready for audits, handovers, or onboarding new team members.
Schemity diffs your ERD against the live database and generates the exact SQL migration. Your ERD lives as plain JSON in your repo - no third-party server ever sees your schema.
Ready to download. No IT ticket. A lightweight ERD tool running in seconds on any corporate laptop.
Download Free TrialAn ERD tool with no cloud means your client's schema never touches a third-party server. What we don't store, we don't have to protect - and you don't have to audit. Safe for NDA projects, client work, and air-gapped environments.
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.
A one-time purchase ERD tool at $129. No subscription, no procurement review, no annual renewal cycle, no per-seat negotiation. Start with a free 2-week trial.
Experience seamless performance and native feel across all major operating systems.
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A lightweight desktop ERD tool. Runs on locked-down laptops, behind VPNs, air-gapped. Document your production database schema in minutes, not weeks. Your ERDs live as JSON in your repo - an offline ERD tool where no third-party server ever sees your data.