Postgres EXPLAIN Visualizer
Decode EXPLAIN plans
Source Input
Processed Output
What is the Postgres EXPLAIN Visualizer?
EXPLAIN ANALYZE output is a wall of nested nodes with costs and timings. This visualizer parses the plan into a readable hierarchy, explains each node type (Seq Scan vs Index Scan, Nested Loop vs Hash Join), highlights where estimated rows diverge from actual (the sign of stale stats), and points at the most expensive node — usually where your missing index belongs.
Frequently Asked Questions (FAQ)
Q: Seq Scan vs Index Scan — which is bad?
Neither, in isolation. Seq Scans are fine for small tables or large fractions of rows; they're a problem on big tables returning few rows.
How to Use the Postgres EXPLAIN Visualizer
- 1Paste your input into the editor above — or start from the preloaded example.
- 2Adjust any options, then click Run to process instantly in your browser.
- 3Review the output panel, then copy, download, or save it as a reusable snippet.