SQL JOIN Visualizer
Edit test data directly, chain multiple tables, and see exactly how each join type behaves. Runs entirely in your browser.
How to use:
- Edit sample data in the tables — or add a third table to chain two joins
- Select a join type (INNER, LEFT, RIGHT, FULL, CROSS)
- Choose the join condition and operator
- See the visual Venn diagram and resulting rows
- Copy the generated SQL for your queries
Edit the tables below to see how different joins behave.
Tables (2/3)
Join step
Step 1: customers ⋈ orders
Returns only rows where the join condition matches on both sides.
3 matched pairs • 1 unmatched in customers • 1 unmatched in orders
Generated SQL
SELECT * FROM customers INNER JOIN orders ON customers.id = orders.customer_id;
Result (3 rows)
| customers.id | customers.name | orders.id | orders.customer_id | orders.product |
|---|---|---|---|---|
| 1 | Alice | 101 | 1 | Widget |
| 1 | Alice | 102 | 1 | Gadget |
| 2 | Bob | 103 | 2 | Gizmo |
About this tool
JOIN Visualizer is a free learning tool that shows exactly how SQL joins behave. Edit the sample tables, pick a join type and condition, and see the matching rows and a Venn diagram update live — then copy the equivalent SQL query.
- Join types
- INNER, LEFT, RIGHT, FULL OUTER, CROSS
- Join conditions
- Single-key conditions with =, !=, >, <, >=, <= operators; each join step can reference any earlier table, and multiple tables can be chained
- Data
- Editable sample tables — add your own rows and columns
- Output
- Resulting rows, a Venn diagram, and the equivalent SQL query to copy
- Signup
- Not required
- Processing
- Entirely in your browser — table data is never uploaded for processing
- Difference
- Interactive Venn diagrams with editable data and 3-table chaining — not static join illustrations
- Price
- Free
Limitations
- Designed for learning join semantics on small illustrative datasets — not a query runner or database client.
JOIN Visualizer — FAQ
Is the JOIN Visualizer free?
Yes. The JOIN Visualizer is completely free with no signup and no usage limits, like all SqlInt mini tools.
How many tables can I join?
Up to 3 tables chained across 2 join steps. Each step can reference any earlier table, so table 1 can join table 3 directly.
Which join types are supported?
INNER, LEFT, RIGHT, FULL OUTER, and CROSS joins with =, !=, >, <, >=, and <= operators — with Venn diagrams and live result rows.
Does my data leave my browser?
No. Every mini tool processes data locally in your browser — pasted text and uploaded files never leave your device.