Explain Plan

A free online EXPLAIN plan visualizer: paste the EXPLAIN output of a PostgreSQL, MySQL/MariaDB, SQLite, SQL Server or Oracle query and explore it as an interactive graph, diagram, table and statistics view — with automatic performance findings.

Everything runs in the browser. No query is ever executed and nothing is uploaded to a server.

Built on @tabularis/explain, the engine behind the Visual EXPLAIN feature of Tabularis, and styled with the same Tabularis dark theme.

Discord — Join our Discord server to talk with the maintainers, share feedback, and get help from the community.

Supported input formats

Engine	Formats
PostgreSQL	EXPLAIN (FORMAT JSON), plain EXPLAIN / EXPLAIN ANALYZE text
MySQL / MariaDB	EXPLAIN FORMAT=JSON, EXPLAIN ANALYZE / ANALYZE FORMAT=TEXT trees
SQLite	EXPLAIN QUERY PLAN — the sqlite3 shell tree (`
SQL Server	SHOWPLAN_XML estimated plans and STATISTICS XML actual plans (ShowPlanXML documents)
Oracle	oracle-plan-json: PLAN_TABLE rows as JSON (see below), or the payload captured by the Tabularis Oracle plugin

The engine can be selected explicitly or auto-detected from the pasted text. SQL Server's ShowPlanXML root element makes its format unambiguous.

Getting an Oracle plan

Oracle has no JSON EXPLAIN output, so the app reads the PLAN_TABLE rows as a JSON document. Run this in SQLPlus, SQLcl or SQL Developer (Oracle 12.2+; in SQLPlus run SET LONG 1000000 first) and paste the returned value. The same query is shown in the app when Oracle is selected (src/lib/oracle-query.ts).

EXPLAIN PLAN FOR SELECT …;

SELECT JSON_OBJECT(
  'version' VALUE 1,
  'statistics' VALUE 'false' FORMAT JSON,
  'plan' VALUE JSON_ARRAYAGG(JSON_OBJECT(
    'id' VALUE id, 'parent_id' VALUE parent_id, 'depth' VALUE depth,
    'position' VALUE position, 'operation' VALUE operation,
    'options' VALUE options, 'object_owner' VALUE object_owner,
    'object_name' VALUE object_name, 'object_alias' VALUE object_alias,
    'object_type' VALUE object_type, 'optimizer' VALUE optimizer,
    'cost' VALUE cost, 'cardinality' VALUE cardinality, 'bytes' VALUE bytes,
    'cpu_cost' VALUE cpu_cost, 'io_cost' VALUE io_cost, 'time' VALUE time,
    'access_predicates' VALUE access_predicates,
    'filter_predicates' VALUE filter_predicates,
    'projection' VALUE projection, 'qblock_name' VALUE qblock_name
    NULL ON NULL RETURNING CLOB)
    ORDER BY id RETURNING CLOB)
  RETURNING CLOB)
FROM plan_table
WHERE plan_id = (SELECT MAX(plan_id) FROM plan_table);

Stack

• Vite + React 19 + TypeScript
• Tailwind CSS 4 with the Tabularis colour tokens
• @tabularis/explain for parsing, analysis and the plan views
• @tabularis/explain-sqlserver for SQL Server SHOWPLAN XML
• @tabularis/explain-oracle for Oracle execution plans
• Vitest + Testing Library for tests

Development

pnpm install
pnpm dev        # local dev server
pnpm test       # run the test suite
pnpm typecheck  # TypeScript only
pnpm build      # typecheck + production build into dist/
pnpm preview    # serve the production build locally

Customizable SEO

All SEO is driven by seo.config.json — title, description, keywords, canonical URL, Open Graph / Twitter cards, robots, theme colour and JSON-LD. The tags are injected into index.html at build time by the seo-inject plugin in vite.config.ts, so customizing the SEO never requires touching the HTML or the app code.

seo.config.json → image points at /og.png; drop a 1200×630 social card into public/og.png (none is committed).

Deploying to Vercel

The site is a fully static single-page build — Vercel auto-detects Vite with zero configuration:

vercel deploy

(Framework preset: Vite, build command pnpm build, output directory dist.)