Free Database Tool
SQL Formatter & Optimizer
Format messy queries, rewrite inefficient patterns and get index suggestions — for MySQL, PostgreSQL, SQLite and SQL Server.
How to use the SQL Optimizer
Make your database faster, one query at a time.
1
Paste your query
Drop in the raw SQL — messy or clean. The tool handles SELECT, INSERT, UPDATE, JOINs, subqueries and window functions.
2
Select your dialect
MySQL, PostgreSQL, SQLite or SQL Server. Syntax and index suggestions differ between them, so choose carefully for accurate output.
3
Review and run
You get a formatted, rewritten query plus a short list of optimizations — index suggestions, LIMIT clauses, avoiding SELECT *. Verify with EXPLAIN before deploying to production.
SQL Optimizer — FAQ
What optimizations does it apply?
It reformats for readability, avoids SELECT *, replaces implicit joins with INNER JOIN, adds LIMIT where sensible, suggests indexes and can rewrite filters or use window functions for cleaner logic.
Will the optimized query return the same results?
Yes — it preserves the query's semantics. It only changes how the database executes the request. Always double-check edge cases and run EXPLAIN before production.
Does it support INSERT and UPDATE?
Yes, and it's most useful on complex SELECT queries. For INSERT/UPDATE it mainly formats and can suggest WHERE improvements to avoid full scans.
Can it help with slow dashboards?
Absolutely. Slow dashboard queries are usually missing indexes, full scans or N+1 patterns — exactly what this tool flags and fixes.