Paste the output of EXPLAIN (FORMAT JSON) from PostgreSQL, MySQL, SQL Server, or Oracle and see it as a readable execution tree, with node types, costs, rows, and timings. The database is auto-detected and nothing leaves your browser.
Works with PostgreSQL, MySQL/MariaDB, SQL Server, and Oracle explain output. The database is auto-detected.
Spot sequential scans, expensive joins, and the nodes where rows and time pile up, at a glance.
Your query plan is parsed locally and never uploaded anywhere.
Every relational database can show you its query execution plan: the tree of operations it uses to run a query, and how expensive each one is. Reading that plan is the core skill for fixing slow SQL, and it's how you decide which indexes to add.
EXPLAIN (ANALYZE, FORMAT JSON) SELECT ...EXPLAIN FORMAT=JSON SELECT ...Run EXPLAIN (ANALYZE, FORMAT JSON) and look at the node tree from the inside out. Watch for Seq Scans on large tables, joins where actual rows far exceed the estimate, and nodes with high total cost or time.
A sequential (full table) scan reads every row; an index scan uses an index to jump to matching rows. On large tables an index scan is usually much faster, so a Seq Scan on a filtered query often signals a missing index.
PostgreSQL, MySQL and MariaDB, SQL Server, and Oracle. The database is auto-detected from the plan, and you can also pick it explicitly.
VisuaLeaf
VisuaLeaf runs EXPLAIN for you and visualizes the plan next to your data and query, across PostgreSQL, MySQL, SQL Server, Oracle and more, with a visual query builder, schema diagrams, and charts.