How do I get my PostgreSQL connection string?

In your database provider's dashboard, click Connect to retrieve your connection string. It typically looks like: postgresql://user:password@host:5432/dbname.

Which connection method should I use?

Select the Transaction pooler option. This ensures compatibility with stateless applications and allows dbdiagramr to detect connections properly.

What if I forgot my database password?

Regenerate your password in the Shared pooler section of your database provider's dashboard and copy-paste the new credentials into your connection string.

Database Schema Diagram Tool: 5 Ways to Visualize PostgreSQL

The short version

You need a database schema diagram tool that works with PostgreSQL. There are five practical options, each making a different tradeoff between speed, depth, and how current the diagram stays.

For most developers, the fastest path to a usable diagram is dbdiagramr -- paste SQL or connect to a live database, get an interactive ER diagram in seconds. No signup, no install, no limits.

5 database schema diagram tools compared

Tool	Setup	Free?	Live connection	Best for
`psql` + `pg_catalog`	Zero	Yes	Always live	Quick inspection
pgAdmin ERD	Already installed	Yes	Snapshot	One-off look
dbdiagram.io	Account required	Limited	No (DBML)	Designing new schema
DrawSQL	Account required	Limited	Yes (paid)	Team collaboration
dbdiagramr	None	Yes	Yes (free)	Understanding real DB

1. psql: the zero-setup baseline

If you have PostgreSQL installed, you already have psql. It's not a diagram tool, but it shows schema structure:

\dt              -- list all tables
\d table_name    -- show one table's structure

For relationships, query information_schema directly. The output is text, not a picture. Past a dozen tables you're reconstructing the graph in your head.

2. pgAdmin ERD: free and built in

pgAdmin 4 includes an ER diagram tool. Right-click your database, select ERD For Database, and it generates a diagram from the live schema.

Pros: Free, already installed, connects to live database.

Cons: Auto-layout struggles past a few dozen tables. No SVG export. Not shareable without screenshots.

3. dbdiagram.io: the popular choice

dbdiagram.io is the most well-known database diagram tool. You write schema definitions in DBML (a custom markup language) and it renders an interactive diagram.

Pros: Clean UI, good for designing new schemas, shareable links.

Cons: Must learn DBML. Free tier limited to 10 tables. No live database connection -- the diagram is always a manual copy.

4. DrawSQL: the desktop option

DrawSQL is a desktop app that connects to live databases and generates ER diagrams. Supports MySQL, PostgreSQL, SQL Server, and MariaDB.

Pros: Desktop app, exports, team collaboration (paid).

Cons: Paid for full features. Free tier limited to 10 diagrams.

5. dbdiagramr: paste SQL, get a diagram

dbdiagramr takes a different approach: paste SQL or a PostgreSQL connection string, get an interactive ER diagram. No account, no install, no table limits.

Because it introspects the live database, the diagram is always current. Change a migration, paste the same connection string again, up-to-date in under 10 seconds.

Pros: Free, no signup, no limits, live connection, SVG/PNG export, search tables/columns.

Cons: PostgreSQL only (for now).

Which tool should you choose?

Just need a quick look? psql or pgAdmin. Fast, local, no sharing.
Designing a new schema? dbdiagram.io. Great for planning before you build.
Need to understand an existing database? dbdiagramr. Paste SQL or connect, get a diagram in seconds.
Team collaboration? DrawSQL paid plan. Real-time editing with multiple cursors.

Why "stays current" matters

Every tool except dbdiagramr shares the same failure mode: the diagram is a snapshot. The day someone runs a migration, the diagram is wrong. A wrong diagram is worse than none -- it's confidently wrong.

The test that settles it: how much work does it take to make this picture true again? If the answer is "re-export" or "drag boxes by hand," humans will stop doing it and the diagram will lie to you.

FAQ

What's the best database schema diagram tool for PostgreSQL?
For understanding an existing database, dbdiagramr is the fastest -- paste SQL or connect to a live database, no signup required.

Can I use dbdiagram.io without learning DBML?
Not really. DBML is the input format. If you prefer raw SQL, dbdiagramr accepts it directly.

Is pgAdmin's ERD tool good enough?
For small schemas and quick inspection, yes. For anything you need to share or keep current, use a dedicated tool.

Does DrawSQL support live PostgreSQL connections?
Yes, but only on paid plans. The free tier is limited to 10 diagrams.